Oxidative coupling of alkylphenols or 1-naphthols catalyzed by metal complexes of diketo compounds
FIELD OF THE INVENTION 
     The present invention relates generally to an improved process for preparing self-condensation products, such as diphenoquinones, biphenols, dinaphthenoquinones and binaphthols from alkylphenols, alkoxyphenols and naphthols and to a catalyst composition for use in said process. More particularly, the invention relates to a method of preparing carbon-carbon coupled condensation products of alkylphenols, alkoxyphenols or 1-naphthols by contacting an aqueous mixture of the phenol or naphthol with oxygen or an oxygen-containing gas optionally in the presence of a surfactant and sufficient alkaline material to sustain a pH in the range of 5-10 during the oxidative coupling reaction and a catalyst system comprising a cupric, cobaltous, manganous or chromic complex of a diketone. 
     DESCRIPTION OF THE PRIOR ART 
     It is well known in the art that substituted phenols can be oxidized to yield self-condensation products, including diphenoquinones, biphenols and polyphenoxy ethers. The procedure employed in the preparation of these derivatives is generally referred to as the oxidative coupling of phenols. 
     The self-condensation products resulting from these oxidative coupling reactions can be catagorized as either the result of carbon-carbon coupling or carbon-oxygen coupling of said phenols. Diphenoquinones and biphenols are prepared by carbon-carbon coupling in accordance with the following general reactions depending upon the reactive sites available in the phenol employed. ##STR1## wherein R is hydrogen or R 1  and wherein R 1  is either alkyl, alkoxy, or another substituent all of which are well known in the art. 
     Similarly, polyphenoxy ethers are prepared by carbon-oxygen coupling in accordance with reactions such as the following general reaction: ##STR2## wherein R and R 1  are as defined above and n is an integer. 
     A variety of materials, including metals and various salts and complexes thereof, have previously been disclosed as useful in promoting the oxidative coupling of alkylphenols. Thus, U.S. Pat. No. 2,785,188, discloses that copper powder may be utilized to prepare diphenoquinones from 2,6-dialkyl-4-halophenols. Similarly, various copper salts and combinations or complexes prepared from copper salts and a variety of nitrogen-containing compounds have been disclosed as useful in the preparation of both diphenoquinones and polyphenoxy ethers. These include, for example, cupric complexes of primary and secondary amines (U.S. Pat. No. 3,306,874); and cupric complexes of tertiary amines (U.S. Pat. No. 3,306,875 and U.S. Pat. No. 3,134,753). The use of cupric salts of carboxylic acids as the oxidizing agent in oxidative coupling reactions is also disclosed in the art. See, in the regard, U.S. Pat. No. 3,247,262. 
     The use of manganese amine chelates as oxidizing agents in oxidative coupling reactions is described in U.S. Pat. No. 3,825,521. 
     A variety of basic compounds have also been employed in oxidative coupling reactions. In many of these, such as those disclosed in U.S. Pat. No. 2,905,674, and in U.S. Pat. No. 2,785,188, the function of the alkaline material was to react with an acidic component, such as HCl, liberated during the course of the reaction and, therefore, a stoichiometric amount of the base was used. 
     It should be noted that, previous methods of preparing coupled products from alkyl- or alkoxy-phenols have required the use of either organic solvents or stoichiometric amounts of organic oxidizing reagents. The present invention provides for a metal keto chelate catalyst system useful in the preparation of carbon-carbon coupled phenols or naphthols is an aqueous reaction medium. Also, with most of the prior art systems the resulting product or products were determined by the particular catalyst employed and could not easily be controlled. The present invention provides for a system which can be readily modified to produce either the biphenol or diphenoquinone directly from the reaction mixture. 
     In accordance with the present invention, it has been found that &#34;alkyl- or alkoxy- phenols&#34; and &#34;1-naphthols&#34; may be oxidatively coupled in a substantially basic aqueous medium if there is employed as a catalyst a system comprising a cupric, cobaltous, manganous or chromic chelate of diketo or keto ester compounds having the structural formula ##STR3## wherein R 1  and R 5  may be independently linear, branched or cyclic alkyl or alkoxy or may be joined together to form a saturated or unsaturated cyclic compound; R 2 , R 3 , and R 4  may be independently hydrogen, halogen, alkoxy, aryl; and n is 0 or 1. 
     It has also been found that the type of product which is produced can be controlled by the amount of alkaline material and by the amount of catalyst employed in the catalyst system. By comparison, the prior art catalysts and processes employing said catalysts have a number of disadvantages which have restricted the utility of said catalysts and processes. These include (a) the requirement that the reaction be conducted in an organic solvent, (b) the fact that the primary product produced is often the polyphenoxy ether, and (c) the inability to form the biphenol, bisphenol or binaphthol derivative directly and in substantial quantities without requiring that this material be produced by a subsequent hydrogenation of the diphenoquinone, stilbenequinone or dinaphthenoquinone prepared in the oxidative coupling reaction. These disadvantages have been overcome by the use of the catalyst and process of the present invention as is described in detail hereinafter. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, condensation products such as diphenoquinones, stilbenequinones, bisphenols, biphenols, dinaphthenoquinones and binaphthols are selectively prepared by contacting a substantially basic aqueous mixture of an &#34;alkylphenol&#34;, an &#34;alkoxyphenol&#34; or a &#34;1-naphthol&#34; with oxygen or an oxygen-containing gas in the presence of a catalyst composition comprising a cupric, cobaltous, manganous or chromic complex of a diketone or keto ester having the structural formula ##STR4## wherein R 1 , R 2 , R 3 , R 4 , R 5  and n have the aforestated values. In a preferred embodiment the aqueous mixtures additionally contain a surfactant. The phenols or naphthols, metal chelate complexes, and alkaline materials which may be utilized are critical to the present invention and are described in detail below. 
     PHENOLS/NAPHTHOLS 
     The phenols which may be employed in carrying out the present invention include both alkylphenols and alkoxyphenols. Specific phenols which may be utilized are described in detail below. 
     The alkylphenols which may be utilized are defined as any alkylphenol having at least two alkyl substituents, with the proviso that the phenols which have only two alkyl substituents must have the substituents in the ortho, ortho(2,6 in the formula below) or ortho, para(2,4 in the formula below) positions. These phenols are frequently referred to by the position of the alkyl substituent or substituents on the benzene ring as set forth in the following formula: ##STR5## 
     The process of the invention is applicable to any alkyl phenol having at least two alkyl substituents and steric properties such as to permit a coupling reaction. Thus if the para position is substituted with an alkyl group other than a methyl group, at least one ortho position must be unsubstituted. If one ortho and the the para position are substituted, at least one of those substitutions must be a tertiary alkyl group. If both ortho positions are substituted, the para position must be either unsubstituted or substituted with a methyl group and no more than one meta position may be substituted with a tertiary alkyl group. 
     Thus, the alkylphenols will have one of the following formulas: ##STR6## wherein R 2  and R 6  are alkyl and R 3 , and R 5  are hydrogen or alkyl, and R 4  is hydrogen with the proviso that R 3  and R 5  cannot both be tertiary alkyl, and that R 2  and R 6  cannot both be tertiary alkyl. ##STR7## wherein R 2  and R 4  are alkyl, provided that at least one of said alkyl groups is a tertiary alkyl and R 3  and R 5  are hydrogen or alkyl. 
     As used herein, the term alkyl refers to any monovalent radical derived from a saturated aliphatic hydrocarbon by removal of one hydrogen atom therefrom. The term includes both straight chain and branched chain materials containing from 1 to about 12 carbon atoms. Preferred results are achieved with alkylphenols wherein the alkyl substituent contains from 1 to about 5 carbon atoms. 
     The alkyl substituents are referred to herein as primary, secondary or tertiary alkyl depending upon the greatest number of carbon atoms attached to any single carbon atom in the chain. 
     Condensation products of any alkylphenol coming within the above-mentioned definition may be prepared in accordance with the present invention. As is apparent from that definition, the alkylphenols include dialkylphenols, trialkylphenols, and tetraalkylphenols. Specifically, the phenols which may be utilized include the following: 
     Ortho, para-substituted phenols including 2,4-dialkylphenols, 2,3,4-trialkylphenols, 2,4,5-trialkylphenols, and 2,3,4,5-tetraalkylphenols wherein the alkyl groups are either methyl or a primary, secondary, or tertiary alkyl provided that at least one of the alkyl groups in either the 2 or the 4 position is a tertiary alkyl, and ortho, ortho-substituted phenols including 2,6-dialkylphenols, 2,3,6-trialkylphenols and 2,3,5,6-tetraalkylphenols wherein the alkyl groups are either methyl or a primary, secondary, or tertiary alkyl provided that in the case of 2,3,5,6-tetraalkylphenols at least one of the alkyl groups in either the 3 or the 5 position is either a primary or secondary alkyl. 
     Representative ortho, para-substituted phenols which may be used include, for example 2,4-ditertiary-butylphenol, 2-methyl-4-tertiary-butylphenol, 2-tertiary-butyl-4-methylphenol, 2,4-ditertiary-amylphenol, 2,4-ditertiary-hexylphenol, 2-isopropyl-4-tertiary-butylphenol, 2-secondary-butyl-4-tertiary-butylphenol, 2-tertiary-butyl-3-ethyl-4-methylphenol, 2,5-dimethyl-4-tertiary-butylphenol, and 2-methyl-3-ethyl-4-tertiary-butylphenol. 
     Representative 2,6-dialkylphenols (ortho, ortho-substituted) include, for example 2,6-xylenol, 2-methyl-6-butylphenol, 2,6-diisobutylphenol, 2-octyl-6-methylphenol, 2-isobutyl-6-dodecylphenol, 2-ethyl-6-methylphenol, 2-methyl-6-tertiary-butylphenol, 2,6-diisopropylphenol, 2,6-disecondary-butylphenol, and 2-cyclohexyl-6-methylphenol. 
     Representative 2,3,6-trialkylphenols which may be utilized in accordance with the present invention include, for example, 2,3,6-trimethylphenol, 2,3,6-triethylphenol, 2,6-dimethyl-3-ethylphenol, 2,3-diethyl-6-tertiary-butylphenol. 
     Representative 2,3,5,6-tetraalkylphenols which may be utilized in accordance with the present invention include, for example, 2,3,5,6-tetramethylphenol, 2,3,5-trimethyl-6-tertiary-butylphenol, 2,3,6-trimethyl-5-tertiary-butylphenol, 2,3-dimethyl-5,6-diethylphenol, and 2-methyl-3-ethyl-5-isopropyl-6-butylphenol. 
     When an ortho, para substituted alkylphenol is employed the coupling reaction proceeds in accordance with the following reaction resulting in the o, o&#39;-coupled product. ##STR8## In this reaction each R represents hydrogen or an alkyl group as defined above depending upon whether di, tri, or tetra substituted alkylphenol is utilized. 
     Similarly, with the ortho, ortho-substituted alkylphenols, the reaction results in the p,p&#39;-coupled product in accordance with the following reaction wherein R is hydrogen or alkyl depending upon wich of the above-mentioned alkylphenols is used as the starting material. ##STR9## 
     It has also been found that alkoxyphenols may be oxidatively coupled in accordance with the present invention. These include among others 2,6-disubstituted phenols wherein at least one of the substituents is an alkoxy group containing up to about six carbon atoms such as methoxy, ethoxy, propoxy, butoxy and pentoxy. In addition to the 2,6-dialkoxyphenols, 2-alkyl-6-alkoxyphenols, wherein the alkyl groups are as defined above for the alkylphenols, may be utilized. As used herein the term alkoxyphenols is intended to include both types of compounds. These compounds may be representated by the following general formulas: ##STR10## wherein each R is any alkyl group as defined above for the alkylphenols or OR and R 1  is either hydrogen or methyl, provided that the substituents adjacent to R 1  and OH cannot both be tertiary alkyl or tertiary alkoxy. Representative alkoxyphenols which may be utilized include, for example, 2,6-dimethoxyphenol, 2,6-diethoxyphenol, 2,6-dibutoxyphenol, 2-methoxy-6-pentoxyphenol, 2-methyl-6-methoxyphenol and 2-ethyl-6-propoxyphenol, 2-methoxy-3-ethoxy-6-methylphenol. 
     When these phenols are utilized the reaction proceeds in accordance with the following representative reaction resulting in the p,p&#39;-coupled material. ##STR11## 
     Mixtures of 2 different phenols may also be utilized. When this is done, there generally results a mixture of three different materials. Two of these are the products of the oxidative coupling of one molecule of one of the phenols with a second molecule of the same phenol. The third product is that resulting from the oxidative coupling of one molecule of the first phenol with one molecule of the second phenol. The products may be separated prior to use, as is well understood in the art. 
     Moreover, 1-naphthol and substituted 1-naphthols having at least 1 unsubstituted position ortho or para to the hydroxyl group may also be employed. The naphthols which may be coupled in accordance with the present invention are represented by the following general formula: ##STR12## wherein 
     R 2 , R 3  and R 4  are hydrogen, alkyl containing from 1 to 5 carbon atoms, or alkoxy containing from 1 to 6 carbon atoms, provided that either or both R 2  or R 4  are hydrogen and R 5 , R 6 , R 7 , and R 8  are hydrogen, alkyl containing from 1 to 5 carbon atoms or alkoxy containing from 1 to 6 carbon atoms provided that tertiary alkyl or tertiary alkoxy groups may not be attached to adjacent carbon atoms of the naphthalene molecule. 
     Representative naphthols which may be utilized include, for example, 1-naphthol, 2-methyl-1-naphthol, 2,3-dimethyl-1-naphthol, 4-ethyl-1-naphthol, and 2-methoxy-1-naphthol. 
     When a naphthol is employed, the coupling reaction takes place in accordance with the following general reactions depending upon the reactive positions -- i.e., those either ortho or para to the hydroxy group -- available. Thus, if R 2  is hydrogen and R 4  is alkyl or alkoxy ##STR13## Similarly, if R 4  is hydrogen and R 2  is alkyl or alkoxy, the products are the 4,4&#39;-binaphthol and the 4,4&#39;-dinaphthenoquinone. When both R 2  and R 4  are hydrogen the products may be a mixture of the 2,2&#39;-; 2,4&#39;- and 4,4&#39;-binaphthols and dinaphthenoquinones. 
     Finally, the catalyst system of this invention may also be employed to prepare coupled products of alkylphenols wherein all of the positions ortho and para to the hydroxy group are substituted and the substituent para to the hydroxy gorup is methyl. These alkylphenols may be represented by the following general formula: ##STR14## wherein 
     R 3  is hydrogen, a primary, secondary or tertiary alkyl or an alkoxy group: 
     R 5  is a primary or secondary alkyl group containing from 1-5 carbon atoms and R 2  and R 6  are a primary, secondary or tertiary alkyl or an alkoxy group, but R 2  and R 6  may not both be tertiary. 
     Representative compounds which may be employed include, for example 2,4,6-trimethylphenol; 2,6-di-secondary-butyl-4-methylphenol; 2-methyl-6-t-butyl-4-methylphenol; and 2,3,4,6-tetramethylphenol. 
     When one of these alkylphenols is employed the reaction proceeds in accordance with the following general reaction to produce the stilbenequinone or bisphenol derivative. These materials are useful in the same applications set forth above for the diphenoquinones, dinaphthenoquinones, biphenols and binaphthols. ##STR15## where the values for the substituents are those specified in formula V. 
     It should be specifically noted that the term &#34;alkyl phenol&#34; is hereby defined as only those alkyl phenols of formulas I, II, and V and their isomers, the term &#34;alkoxy phenol&#34; is hereby defined as only those alkoxy phenols of formula III and their isomers and that the term &#34;1-naphthol&#34; is defined as only those 1-naphthols of formula IV and their isomers. 
     One of the essential components of the catalyst system of the present invention is a metal beta or gamma diketo or keto ester enolate. The metal source for this complex is a cupric, chromic, manganous or cobaltous ion which, may be conveniently be added to the diketones as for example as acetates, formates or chlorides. 
     The beta and gamma diketones or keto esters that have been found useful in the process of the present invention may be represented by the following structural formula: ##STR16## wherein R 1  and R 5  may be independently linear branched or cyclic alkyl or alkoxy or may be joined together to form a saturated or unsaturated cyclic compound; 
     R 2 , R 3  and R 4  may be independently hydrogen, halogen, alkoxy, substituted or unsubstituted alkyl, aryl; and n is 0 or 1. Useful beta and gamma diketones include those having the following formulas: ##STR17## 
     The metal chelates are prepared by reacting the diketones with a source of the appropriate metal ions. The metal ion source may include various metal salts including halides, halo hydroxides, carboxylates, acetates, nitrates, sulfates, alkyl sulfates, aryl sulfates, carbonates, hydroxides or chlorates. 
     Many of the chelates are commercially available but those that are not may be prepared in any manner and the preparation thereof has not been found to be critical to the present invention. Similarly the ratio of diketones to metal source has been found to be not narrowly critical. It should be noted however that if the ratio of diketone to metal source is less than one, less complex is formed. The following three methods have been employed but other methods, which will be readily apparent to those skilled in the art from the description of the invention given herein, may also be utilized. 
     First, suitable amounts of the diketones and a source of cupric, chromic, manganous or cobaltous ions may be combined in a suitable medium such as water and reacted to form the chelate. The chelate is prepared by simply stirring the solution for a period of time. If desired, heat may be applied to accelerate formation of the chelate. 
     Alternatively, the diketones and the source of the metal ion may simply be combined and added to the reaction mixture wherein the chelate of the diketone is formed. When this is done any basic compound required to neutralize acidic by-products of the chelates forming reaction is also added directly to the reaction mixture. 
     Finally, the diketone, the source of metal ion, and any required basic compound may be added separately to the reaction medium and the complex formed in situ. As mentioned above, the method by which the metal complex is prepared has not been found to be critical to the present invention. However, further improved conversion results have been achieved when the source of metal ion and the diketone are combined prior to addition to the reaction medium. 
     The amount of metal chelate employed has not been found to be narrowly critical to the process of the present invention. However, it is preferred to employ at least .02 mmols of the chelate per 100 mmols of alkylphenol. If less than this amount is used the reaction is slower and the yields are low. Similarly, the maximum amount of chelate employed is not generally greater than 1 mmols of the complex per 100 mmol of alkylphenol. At amounts much in excess of this the cost of the catalyst results in a uneconomic system. Higher levels of catalysts within the range of .02 to 1 mmols per 100 mmols of alkylphenols tend to favor diphenoquinone formation. 
     Although any of the above-mentioned metal chelate may be used, improved conversion results have been achieved with the cupric complexes of acetyl acetone. 
     As mentioned above, an advantage of the catalyst system and of the process of the present invention is that the reaction can be carried out in an aqueous medium instead of an organic solvent as has been used in prior art systems. However, it has not been found to be critical to the present invention to employ a water soluble metal complex. Thus, materials which are insoluble in water as well as those which are soluble may be utilized. 
     SURFACTANT 
     The catalyst composition of the present invention may also include, as an optional component thereof, a surfactant. The presence of a surfactant aids in the dispersion of the solid products thereby moderately improving conversion results. Additionally the surfactant allows for easier cleaning of large reactors. A variety of surfactants, also known as dispersants, are well known in the art and, as used herein, the term surfactant is intended to refer to organic compounds that contain in the molecule both hydrophobic and hydrophilic groups. 
     Surfactants are often classified, based on the hydrophilic (water liking) group which they contain, as either anionic, cationic, nonionic, or amphoteric. Any such surfactants may be employed in the present invention. 
     Surfactants are discussed in detail in the Encyclopedia of Chemical Technology, Kirk-Othmer, Second Edition Vol. 19 at pages 508-589, any of the surfactants described therein may be utilized in the present invention. 
     The amount of surfactant employed has not been found to be critical to the utility of the catalyst system in carrying out the improved process of the present invention. However, if the use of a surfactant is desirable such as for example to increase the amount of carbon-carbon coupled product, there should be included in the reaction mixture at least about 0.2 mmols of surfactant per 400 mmol of phenol or naphthol. Preferred conversion results are achieved when the amount of surfactant employed is equal to from about 0.2 to about 0.6 mmols of surfactant per 400 mmol of phenol or naphthol. Additional amounts of the surfactant may be employed; however, the use of greater amounts of surfactant has usually not been found to significantly increase the total yield of product and it is, therefore, not generally desirable to include additional material in the reaction mixture. When a cupric alkyl sulfate as defined above is employed, both as the metal ion source and as the surfactant, the amount of said material employed is preferably equal to at least 0.2 mmols per 400 mmol of phenol or naphthol -- i.e., the preferred amount of metal compound plus the preferred amount of surfactant. 
     ALKALINE MATERIAL 
     In accordance with the present invention, an alkaline material is also included in the catalyst composition to ensure that the pH during the reaction is maintained in the range of 5-10. It has been found that the use of an alkaline material to raise the pH in the present system increases the conversion to carbon-carbon coupled products and decreases the conversion to carbon-oxygen coupled products. The use of such a material to maintain the required pH also increases the rate of the oxidative coupling reaction and decreases the amount of the metal compound which must be utilized. 
     The alkaline material useful in achieving the pH of the reaction and the improved results of the present invention is selected from the group consisting of alkali metal hydroxides, alkali metal carbonates, and alkali metal bicarbonates. The alkaline material may be added either as a single compound or as a mixture of compounds. Representative materials which may be employed include, for example, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, lithium carbonate, sodium bicarbonate, rubidium carbonate, rubidium hydroxide, cesium bicarbonate, and cesium hydroxide. 
     The amount of alkaline material employed has not been found to be narrowly critical to the present invention as long as the required pH range is maintained. However, preferred results are achieved when the amount of said material is equal to at least about 3 millimols per mol of phenol or naphthol. Smaller amounts of alkaline material will normally result in a reaction pH of less than 5 and will normally cause a low molar conversion of starting compound to final product. A preferred pH range is from about 8 to 9.5. Increased amounts of alkaline material may also be utilized in carrying out the present invention. It has been found that, for a given set of reaction conditions, increasing the amount of alkaline material increases the total conversion to carbon-carbon coupled products and the relative amount of diphenoquinone, stilbenequinone, or dinaphthenoquinone as compared to the amount of biphenol, bisphenol or binaphthol. Thus, by varying the amount of alkaline material to vary the pH within the required pH range of 5-10, the type of product can be controlled. 
     Besides the selective production of carbon-carbon coupled products, an additional advantage of the catalyst system of the present invention is the ability to control the type of carbon/carbon coupled product produced. Thus, it is possible to prepare selectively either diphenoquinone or biphenol, stilbenequinone, or bisphenol, or dinaphthenoquinone or binaphthol, in accordance with the present invention. This result is achieved by controlling the amount of alkaline material included in the system. Generally, as the amount of alkaline material is increased, the percentage of quinone derivative produced also increases. Therefore to obtain larger amounts of biphenolic product as opposed to quinone derivatives it is desirable to use sufficient alkaline material to raise the pH of the reaction material to a range of about 7-10, preferably 7.5-9.5. Higher pH values resulted in significant levels of oligomer formation. (carbon-oxygen coupled products.) 
     REACTION CONDITIONS 
     As mentioned above, an advantage of the catalyst system and process of the present invention is that it makes it possible for the oxidative coupling reaction to be carried out in an aqueous medium. The amount of water employed has not been found to be critical to the present invention and any amount of water which will permit the reaction mixture to be stirred during the course of the reaction may be employed. It should also be noted again that it is not essential that the various components be soluble in water and the term aqueous mixture as used herein is intended to include solutions, slurries, suspensions and the like. 
     The components of the reaction mixture may be combined in any suitable manner. Thus, the phenol or naphthol, surfactant, metal complex, alkaline material and water may be combined in any order in a suitable reaction vessel. Alternatively, and in a preferred method, the phenol or naphthol and optionally the surfactant are combined in water in a suitable reaction vessel, the mixture is stirred rapidly, preferably by utilizing a stainless steel impeller turning at 3,000-10,000 RPM and an aqueous mixture of the metal salt compound and diketone is added, followed by an aqueous solution of the alkaline material to maintain desired pH. 
     In modifications of this procedure the metal complex may be added prior to heating or the metal complex and some alkaline material may particularly at low pH ranges be combined prior to addition to the reaction mixture. 
     The reaction mixture comprising phenol or naphthol, water metal complex and alkaline material is contacted with a suitable oxidizing agent to convert the phenol or naphthol to the desired product. Oxidizing agents which may be employed in carrying out the present invention include oxygen either alone or as an oxygen-containing gas, such as air. The oxygen may be introduced into the reaction mixture either directly as oxygen gas or as an oxygen-generating material such as ozone, hydrogen peroxide, or an organic peroxide. The amount of oxygen utilized should be sufficient to obtain the desired conversion of the phenol or naphthol to the coupled product. To assure that sufficient oxygen is present, oxygen should be introduced into the reaction mixture continuously during the course of the reaction. 
     The reaction conditions -- i.e., time and temperature -- employed have not been found to be narrowly critical to the process of the present invention. Preferred results have been achieved when the reaction mixture is maintained at from about 80° C. to 90° C. during the course of the reaction. However, temperatures above and below this preferred range may be utilized. At lower temperatures the reaction rate is reduced and at temperatures below about 40° C. it is so slow as to result in an uneconomic system. When operating at atmospheric pressure, as is desirable in some commercial operations, the practical upper limit on the temperature is 100° C., the boiling point of the water. 
     If the reaction is conducted at increased oxygen pressure, the reaction time is decreased, the total yield of coupled product is usually increased, and the relative amount of quinone derivative is also usually increased. 
     The amount of time required for completion of the reaction depends on the temperature employed and other variables such as the pressure, concentration of phenol or naphthol and the amount of metal complex, surfactant if present, and alkaline material employed. However, it has been found that, when conducted at atmospheric pressure, the reaction is usually completed in 6 hours or less. 
     Although, as mentioned above, the process of the present invention results primarily in the production of carbon-carbon coupled products, there are also sometimes included in the solids removed from the reaction mixture the following: (a) unreacted phenol or naphthol, and (b) low molecular weight polyphenoxy ether. The polyphenoxy ether and phenol or naphthol may be removed by washing the solids with a solvent in which these materials are soluble, such as an aromatic hydrocarbon -- e.g., toluene, benzene, or a halogenated solvent -- e.g., methylene chloride. If it is desired to separate the materials from each other and from the solvent, this may be done by distillation. 
     If the reaction results in the mixture of biphenol and diphenoquinone, bisphenol and stilbene quinone, or binaphthol and dinaphthenoquinone, these materials may be separated by any method known in the art. An especially convenient way of separating the materials is to stir the solid product with a dilute aqueous solution of sodium hydroxide, which converts the biphenol, bisphenol or binaphthol to the sodium salt which is usually soluble in water. The insoluble diphenoquinone, stilbene quinone or dinaphthenoquinone may then be filtered off and the biphenol, bisphenol or binaphthol recovered by adding the aqueous solution of the sodium salt thereof to a dilute solution of a strong acid such as hydrochloric acid from which the biphenol, bisphenol or binaphthol precipitates. Alternatively, the entire product may be hydrogenated or chemically reduced and converted to only the biphenol, bisphenol or binaphthol. 
     The diphenoquinones and/or biphenols as well as the binaphthols, bisphenols and dinaphthenoquinones and stilbene quinones produced in accordance with the present invention are suitable for any of the uses of these materials which have heretofore been described in the art. Thus, the diphenoquinones and dinaphthenoquinones may be used as inhibitors of oxidation, peroxidation, polymerization and gum formation in gasolines, aldehydes, fatty oils, lubricating oils, ethers and similar compounds as mentioned in U.S. Pat. No. 2,905,674 issued to Filbey. The diphenoquinones may also be hydrogenated, employing conventional techniques, to yield the corresponding biphenol. The biphenols may be employed as stabilizers in gasoline and other petroleum products as described in U.S. Pat. No. 2,479,948 issued to Luten et al. They may also be utilized as intermediates in the manufacture of such useful products as sulfones, carbonates and epoxy resins. In order to describe the present invention so it may be more clearly understood the following examples are set forth. These examples are given primarily for the purpose of illustration and any enumeration of detail contained therein should not be interpreted as a limitation on the concept of the present invention. 
    
    
     EXAMPLE I 
     Into a first flask there were added: 
     0.74 grams (2 mmols) of cupric 
     1,1,1-trifluoroacetylacetone, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketo complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 0.672 gms of sodium bicarbonate (as a 8 ml of 1.0 N) solution was added over a period of 3 minutes. At this point the pH of a sample of the mixture was found to be 8.4. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Thermo-O-Watch temperature controller. 
     The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature and filtered to remove the water phase, washed once with 200 ml water. The water phase had a pH of 7.5. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 37.5 weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 24.3 gm of product was obtained as a yellow solid which contained almost no diphenoquinone and 99+ weight percent tetramethylbiphenol. 
     EXAMPLE 2 
     Into a first flask there were added: 
     0.96 grams (2 mmols) of cupric 1,1,1,5,5,5-hexafluoroacetylacetone. 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; .1 gram of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 2.068 gms of sodium carbonate (as a 28 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that no 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 40.3 gm. product was obtained as a yellow solid which contained 34.9 weight percent diphenoquinone and 65 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 3 
     Into a first flask there were added; 
     0.4 grams (2 mmols) of cupric acetate Cu(OAc) 2 .H 2  O, 
     1.18 grams (4 mmols) of a compound having the structural formula ##STR18## 25 grams of ion exchange water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; .1 grams of sodium lauryl, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketo complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 3.975 gms of sodium carbonate (as 37.5 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hours, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature acidified to pH 3 with HCl, filtered to remove the water phase, washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 8.3 mol percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol oligomer and dried at 60° C. overnight. 33.9 g of the product was obtained as a yellow solid which contained almost no diphenoquinone and 99.+ weight percent tetramethylbiphenol. 
     EXAMPLE 4 
     Into a first flask there were added: 
     0.4 grams (2 mmols) of cupric acetate Cu(OAc) 2 .H 2  O, 
     0.74 grams (4 mmols) of a compound having the structural formula ##STR19## 25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex slurry prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 4.346 gms of sodium carbonate (as 41 ml of 1.0 N) solution was added during the course of the reaction to maintain pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 20.7 weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 31.0 gm. of product was obtained as a light tan solid which contained almost no diphenoquinone and 99+ weight percent tetramethylbiphenol. 
     EXAMPLE 5 
     Into a first flask there were added; 
     0.4 grams (2 mmols) of cupric acetate Cu(OAc) 2 .H 2  O, 
     0.52 grams (4 mmols) of 3-ethylacetylacetone, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex slurry prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. 3.816 gms of sodium carbonate (as 36 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that about 1.0 weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 37.4 gm of product was obtained as a green solid which contained 40.6 weight percent diphenoquinone and about 59 weight tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 6 
     Into a first flask there were added: 
     0.4 grams (2 mmols) of cupric acetate Cu(OAc) 2 .H 2  O, 
     0.72 grams (4 mmols) of 3-phenylacetylacetone, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there where added; .1 grams of sodium lauryl sulfate 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex slurry prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. 4.770 gms of sodium carbonate (as 45 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated about 1.0 weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 37.8 gm of product was obtained as a green solid which contained 50.6 weight diphenoquinone and 49.4 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 7 
     Into a first flask there were added; 
     0.77 grams (2 mmols) of cupric benzoylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 0.672 gms of sodium bicarbonate (as 8 ml of 1.0 N) solution was added over a period of 3 minutes. At this point a sample of the mixture had a pH of 8.7. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature and filtered to remove the water phase, washed once with 200 ml water. The water phase had a pH of 8.0. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 28.3 weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 30.1 gm of product was obtained as a yellow solid which contained almost no diphenoquinone and 99.+ weight percent tetramethylbiphenol. 
     EXAMPLE 8 
     Into a first flask there were added; 
     0.4 grams (2 mmols) of cupric acetate Cu(OAc) 2 .H 2  O, 
     0.46 grams (4 mmols) of acetonylacetone, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 2.52 gms of sodium bicarbonate (as 30 ml of 1.0 N) solution was added over a period of 3 minutes. At this point the pH of a sample of the mixture was found to be 7.6. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature and the water phase had a pH of 8.5. The mixture was acidified to pH 4.5 with HCl and filtered to remove the water phase, washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 6.2 weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 33.7 gm of product was obtained as a high tan solid which contained almost no diphenoquinone and 99.+ weight percent tetramethylbiphenol. 
     EXAMPLE 9 
     Into a first flask there were added; 
     0.4 grams (2 mmols) of cupric acetate Cu(OAc) 2 .H 2  O, 
     0.87 grams (4 mmols) of 97% 1,3-cyclohexanedione, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. 4.452 gms of sodium carbonate (as 42 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that all of the 2,6-xylenol had reacted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 42.3 gm of product was obtained as a dark green solid which contained 43.1 weight percent diphenoquinone and 57.3 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 10 
     Into a first flask there were added; 
     0.75 grams (2 mmols) of chromium acetylacetonate (Cr(AA) 3 ), 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred chromic diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 1.344 gms of sodium bicarbonate (as 16 ml of 1.0 N) solution was added over a period of 3 minutes. At this point the pH of a sample of the mixture was found to be 8.8. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature and filtered to remove the water phase, and the water phase had a pH of 8.6. The solid was slurried with HCl (pH 2.6), fitted, and washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 87.9 weight percent of the 2,6-xylenol was converted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. The product (23.1 gram), light gold color, contained almost no diphenoquinone and 99+ weight percent tetramethylbiphenol. 
     EXAMPLE 11 
     Into a first flask there were added; 
     0.75 grams (2 mmols) of Cr 3  acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred chromic diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 2.915 gms of sodium carbonate (as 27.5 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed once with 200 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 3.9 mol percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. The product (32.3 grams) contained almost no diphenoquinone and 99+ weight percent tetramethylbiphenol. 
     EXAMPLE 12 
     Into a first flask there were added; 
     0.49 grams (2.0 mmols) of manganese acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred manganous diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 1.344 gms of sodium bicarbonate (as 16 ml of 1.0 N) solution was added over a period of 3 minutes. At this point the pH of a sample of the mixture was found to be 8.7. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature filtered to remove the water phase and the water phase had a pH of 8.4. The solid was stirred with HCl-H 2  O to pH 4.9, filtered, and washed once with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 31.3 weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 10.1 gm of product was obtained as a yellow solid which contained almost no diphenoquinone and 99+ weight percent tetramethylbiphenol. 
     EXAMPLE 13 
     Into a first flask there were added; 
     0.49 grams (2 mmols) of manganous acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred manganese diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 4.180 gms of sodium carbonate (as a 30 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99 mol percent of the 2,6-xylenol was converted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 30.2 gm. product was obtained as a yellow solid which contained 6.1 weight percent diphenoquinone and 93.9 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 14 
     Into a first flask there were added; 
     0.52 grams (2 mmols) of cobaltous acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 gram of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred cobalt diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 1.3442 gms of sodium bicarbonate (as 16 ml of 1.0 N) solution was added over a period of 3 minutes. At this point the pH of a sample of the mixture was found to be 8.8. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hours, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature and filtered to remove the water phase, and the water phase had a pH of 9.1. The solid was slurried with HCl at pH 4, filtered, and washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 48.2 weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 20.0 g of the product was obtained as a light tan solid which contained almost no diphenoquinone and 99+ weight percent tetramethylbiphenol diphe 
     EXAMPLE 15 
     Into a first flask there were added; 
     0.52 grams (2 mmols) of cobaltous acetylacetone, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred cobalt diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 20.014 gms of sodium carbonate (as 19 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 13.5 mol percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 25.4 gm. of product was obtained as a brownish solid which contained 5.4 weight percent diphenoquinone and 94.6 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 16 
     Into a first flask there were added; 
     0.64 grams (2 mmols) of cupric ethyl acetoacetate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 0.672 gms of sodium bicarbonate (as 8 ml of 1.0 N) solution was added over a period of 3 minutes. At this point the pH of a sample of the mixture was found to be 8.6. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature and filtered to remove the water phase, washed once with 200 ml with water. The water phase had a pH of 8.7. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 29.5 mol percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 26.8 gm of product was obtained as a yellow solid which contained almost no diphenoquinone and 99+ weight percent tetramethylbiphenol. 
     EXAMPLE 17 
     Into a first flask there were added; 
     0.64 grams (2 mmols) of cupric ethylacetoacetate 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 2.016 gms of sodium bicarbonate (as 24 ml of 1.0 N) solution was added over a period of 3 minutes. At this point the pH of a sample of the mixture was found to be 8.7. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     PRODUCT ISOLATION 
     The reaction slurry was cooled to room temperature and filtered to remove the water phase and the water phase had a pH of 9.1. The solid was slurried in aqueous HCl at pH 5.8, filtered, washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 10.7 mol percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 30.7 gm. of product was obtained as a light tan solid which contained almost no diphenoquinone and 99+ weight percent tetramethylbiphenol. 
     EXAMPLE 18 
     Into a first flask there were added; 
     0.4 grams (2 mmols) of cupric acetate Cu(OAc) 2 .H 2  O, 
     0.67 grams (4 mmols) of ethyl 4-chloroacetoacetate, 
     25 grams of ion exchange water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex slurry prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 3.922 gms of sodium carbonate (as 37 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,6-xylenol was converted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 41.1 gm of product was obtained as a yellow solid which contained 44.8 weight percent diphenoquinone and 55 wight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 19 
     Into a first flask there were added; 
     0.4 grams (2 mmols) of cupric acetate Cu(OAc) 2 .H 2  O, 
     0.68 grams (4 mmols) of 97% ethyl 2-chloroacetoacetate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; .1 gm of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. after which 3.922 gms of sodium carbonate (as 37 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 178  hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,6-xylenol was converted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 41.8 gm of product was obtained as a yellow solid which contained 44.6 weight percent diphenoquinone and 55 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 20 
     Into a first flask there were added; 
     1.05 grams (4 mmols) of cupric acetylacetonate (Cu(AA) 2 ), 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes after which 0.672 gms of sodium bicarbonate (as 8 ml of 1.0 N) solution was added over a period of 3 minutes. At this point the pH of a sample of the mixture was found to be 9.1. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 178  hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature and filtered to remove the water phase, washed once with 200 ml water. The water phase had a pH of 8.0. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 15.2 mol percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove xylenol and oligomer and dried at 60° C. overnight. 28.1 gm of product was obtained as a yellow solid which contained 0.15 weight percent diphenoquinone and 99+ weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 21 
     Into a first flask there were added; 
     0.51 grams (2 mmols) of cupric acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. .472 gms of sodium hydroxide (as 11.8 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 8 ± 0.1. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,6-xylenol was converted. 
     The solid product was then washed xylene to remove oligomer and dried at 60° C. overnight. 40.2 gm of product was obtained as a green solid which contained 33 weight percent diphenoquinone and 67 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 22 
     Into a first flask there were added: 
     0.52 grams (2 mmols) of cupric acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. 4.544 gms of sodium hydroxide (as 113.2 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9.5 ± .2. The sample was returned to the reactor which was then heated to 80° C. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Thermo-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,6-xylenol was converted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 33.0 gm of product was obtained as a yellow solid which contained 46.7 weight percent diphenoquinone and 53 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 23 
     Into a first flask there were added; 
     0.52 grams (2 mmols) of cupric acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; .1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 2.162 gms of sodium carbonate (as 20.4 ml of 1.0 N) solution was added over a period of 3 minutes during the course of the reaction to maintain the pH of the mixture at 8 ± 0.1. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified with HCl to pH 3, filtered to remove the water phase, and washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 39.7 gm of product was obtained as a dark green solid which contained 23.2 weight percent diphenoquinone and 77 weight percent tetramethylphenol as determined by spectrophotometric analysis. 
     EXAMPLE 24 
     Into a first flask there were added; 
     0.13 grams (1 mmol) of cupric acetylacetatonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 1.431 gms of sodium bicarbonate (as 13.5 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 8 ± 0.1. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning of flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,6-xylenol was unreacted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 38.1 gm of product was obtained as a green solid which contained 4.2 weight percent diphenoquinone and 95.8 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 25 
     Into a first flask there were added; 
     0.026 grams (0.1 mmols) of cupric acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; .1 grams of sodium lauryl sulfate, 200 grams of deionized water and 48.8 grams (400 mmols) of 2,6-xylenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 1.06 gms of sodium bicarbonate (as 13 of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 8 ± 0.1. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Thermo-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,6-xylenol was converted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 38.7 gm of product was obtained as a green solid which contained 0.8 weight percent diphenoquinone and 99.2 weight percent tetramethylbiphenol as determined by spectrophotometric analysis. 
     EXAMPLE 26 
     Into a first flask there were added; 
     0.52 grams (2 mmols) of cupric acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from abut 3,000 to about 10,000 rpm there were added; 0.2 grams of sodium lauryl sulfate, 200 grams of deionized water and 82.4 grams (400 mmols) of 2,6-di-sec-butyl phenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000  rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 1.802 gms. of sodium carbonate (as 17 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow as reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 16.5 weight percent of the 2,6-di-sec-butyl was unreacted. 
     The solid product was then washed with methanol to remove di-sec-butylphenol and oligomer and dried at 60° C. overnight. 19 gm of product was obtained as a red crystalline solid which contained 100 weight percent of the diphenoquinone. 
     EXAMPLE 27 
     Into a first flask there were added; 
     0.52 grams (2 mmols) of cupric acetylacetone, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.2 grams of sodium lauryl sulfate, 200 grams of deionized water and 82.4 grams (400 mmols) of 2,4-di-tert-butylphenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. 2.756 gms of sodium carbonate (as 26 ml of 1.0 N) solution was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 175 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,4-di-tertbutylphenol was converted. 
     The solid product was then triturated with ethanol to remove oligomer and dried at 60° C. overnight. 52.6 grams of product was obtained as a solid which contained no diphenoquinone and in excess of 99 weight percent of biphenol (M.P. 194° C). 
     EXAMPLE 28 
     Into a first flask there were added; 
     0.52 grams (2 mmols) of cupric acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; .2 grams of sodium lauryl sulfate, 200 grams of deionized water and 62.4 grams (400 mmols) of 2,6-dimethoxyphenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. 2.12 gm. of sodium carbonate (as 20 ml of 1.0 N) solution and than 228 mg NaOH was added as 97% pellets was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, filtered to remove the water phase, and washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the phenol was unreacted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 48.4 gm of product was obtained as a purple solid which contained 46 weight percent diphenoquinone and 54 weight percent of biphenol as determined by spectrophotometric analysis. 
     EXAMPLE 29 
     Into a first flask there were added; 
     0.52 grams (2 mmols) of cupric acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.2 grams of sodium lauryl sulfate, 200 grams of deionized water and 43.3 grams (300 mmols) of 1-naphthol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 5 minutes and heated to 80° C. 2.650 gms of sodium carbonate (as 25 ml of 1.0 N) solution and 21 mg NaOH was added during the course of the reaction to maintain the pH of the mixture at 9. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed reaction time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, and washed twice with 125 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 1-naphthol was converted. 
     The solid product was then washed with xylene to remove oligomer and dried at 60° C. overnight. 41.8 grams of product obtained was a mixture of carbon-carbon coupled products as determined by infrared analysis. 
     EXAMPLE 30 
     Into a first flask there were added; 
     0.52 grams (2 mmols) of cupric acetylacetonate, 
     25 grams of ion exchanged water. 
     Into a 500 ml creased Morton flask, fitted with a gas addition tube, a condenser, a thermometer, and a stirrer capable of operating at speeds in the range of from about 3,000 to about 10,000 rpm there were added; 0.2 grams of sodium lauryl sulfate, 200 grams of deionized water and 55.4 grams (400 mmols) of 2,4,6-trimethylphenol. 
     To the resulting slurry which was stirred using a Labline cruciform stainless steel impeller turning at about 6,000 rpm there was added the stirred copper diketone complex solution prepared above. The resulting mixture was stirred for 15 minutes and heated to 80° C. 0.34 gms of sodium hydroxide (as 21 ml of 1.0 N) solution and 3.7 grams of 97% NaOH pellets was added during the course of the reaction to maintain the pH of the mixture at 9.5 to 10. The mixture was stirred under oxygen. The oxygen flow was rapid at the beginning to flush the system. After about 1/2 hour, oxygen flow was reduced and maintained at a level sufficient to cause slow bubbling in a bubbler attached to the top of the condenser. The temperature was controlled by a Therm-O-Watch. The reaction mixture was stirred vigorously and maintained under oxygen for the prescribed time of 6 hours. 
     Product Isolation 
     The reaction slurry was cooled to room temperature, acidified to pH 3 with HCl, filtered to remove the water phase, washed twice with 150 ml water. A sample of the solid was removed, dissolved in acetone and analyzed by gas-liquid chromatography. The analysis indicated that 99+ weight percent of the 2,4,6-trimethylphenol converted. 
     The solid product was dried at 60° overnight. 31.4 gm of product contained a mixture of stilbenequinone and bisphenol as determined by infrared analysis.