Phenyl-aliphatic oximes as odorants
THE INVENTION 
     The invention concerns novel oximes of the formula ##STR1## wherein R is hydrogen, methyl or ethyl, processes for the manufacture of these compounds, and their use as odorants. 
     Formula I is intended to embrace both the syn- and anti-forms of the oximes, with the anti-form being preferred. 
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The novel oximes of formula I can be prepared by a process which comprises reacting a ketone of the formula ##STR2## wherein R is as defined above, with hydroxylamine or a salt thereof 
     The reaction of a ketone of formula II with hydroxylamine or a salt thereof can be carried out according to methods known per se. (See e.g. Organikum, Organisch-chemisches Grundpraktikum, collective authors; 7th Edition; VEB Deutscher Verlag der Wissenschaften; Berlin 1967, 375, 555.) When the hydroxylamine salt is used the oxime is readily obtained by reacting the ketone with the salt (for example, the hydrochloride or sulphate) in alcoholic solution or aqueous-alcoholic solution containing pyridine or sodium acetate. The reaction temperature is preferably the reflux temperature of the reaction mixture. The resulting oxime can be separated from the reaction mixture by known methods. 
     The working-up is conveniently carried out according to methods known per se: distilling off the majority of the alcohol, adding an organic solvent, washing with water and finally removing the unreacted ketone. 
     The ketone starting materials of formula II are known or can be prepared according to known methods, for example, by chain-lengthening commercially available diisopropyl ketone (e.g. by means of arylalkyl halides). 
     The compounds of formula I have particular organoleptic properties which make them especially suitable as odorant substances. 
     The oximes provided by the present invention are distinguished by a particular combination of perfumistically valuable properties. They are all either colorless (or at most slightly colored), readily accessible, the individual batches are constant in odor, non-irritating, stable, and easy to handle. 
     The compound of formula I are generally reminiscent with respect to odor of notes of blackcurrants, sage, and grapes. The individual olfactory notes are the following: 
     Compound I: 
     
         R═H: 
    
     powerful and long-lasting odor, green, natural, after sage, after blackcurrants, but more flowery; 
     Compound I: 
     
         R═CH.sub.3 : 
    
     powerful and very natural odor after sage, grapes, wine pressing shed; 
     Compound I: 
     
         R═C.sub.2 H.sub.5 : 
    
     powerful and diffusive odor, after blackcurrants. 
     These olfactory notes are quite different from those disclosed for the araliphatic oxime 3-benzylpentan-2-one oxime in Swiss Patent Application No. 645/82 (which became accessible on Aug. 10, 1983 with the publication of European Patent Publication No. 85,352) and which compound is described as smelling like ginger nuts, pyrazine and peas. Additionally, the novel oximes of the present invention are found to be about one hundred times greater in olfactory strength than the known oxime (compounds tested as 1% solutions in isopropyl myristate applied to smelling strips, measured immediately and/or after 24 hours). Thus the novel oximes may be used in more diluted form. 
     On the basis of their natural odor notes and their fixation (long-lasting effect, especially with respect to freshness) they are suitable, in particular, for modifying known compositions, examples of such compositions being: 
     (a) flowery compositions in which, for example, the citrus notes are to be intensified (e.g., for cologne types and the like, as well as extracts), 
     (b) fruity compositions, for example of the currant type (extract types), compositions of the feminine as well as of the masculine direction, 
     (c) compositions with green notes, where especially a desired natural effect is produced, and finally 
     (d) compositions in which generally the character of natural oils is striven for (e.g. lilac or lavender). 
     The compounds of formula I combine with numerous known natural or synthetic ingredients of odorant substance compositions, whereby the range of the natural ingredients can embrace not only readily-volatile but also semi-volatile and slightly-volatile components and the range of the synthetic ingredients can embrace representatives from almost all classes of substances, as will be evident from the following compilation: 
     Natural products, such as angelica seed oil, tree moss absolute, basil oil, mugwort oil, bergamot oil, castoreum, acetylated cedarwood oil (e.g. Vertofix® IFF or Cedartone™ Givaudan), coriander oil, oak moss, elemi oil, galbanum oil, geranium oil, jasmine absolute and its substitute, camomile oil, lavandin oil, lavender oil, mandarin oil, mastix absolute, clove bud oil, neroli oil, patchouli oil, petitgrain oil Paraguay, rose oil, rosemary oil, sandalwood oil, styrax, vetiver oil, wormwood oil, ylang-ylang oil, hyssop oil, civet oil, lemon oil. 
     Alcohols, such as citronellol, dimethylbenzylcarbinol, Dimetol® Giv. (2,6-dimethyl-2-heptanol), geraniol, linalool, menthol, 3-methyl-5-(2&#39;,2&#39;,3&#39;-trimethyl-cyclopent-3&#39;-en-1&#39;-yl)-pentan-2-ol (Sandalore® Givaudan), nerol, phenylethyl alcohol, phenylpropyl alcohol, natural rhodinol, terpineol, a-terpineol, 2,2,8-trimethyl-7-nonen-3-ol, cinnamic alcohol. 
     Aldehydes, such as α-amylcinnamaldehyde, citral, cyclamen aldehyde, decanal, 3,5-dimethyl-cyclohex-3-ene-carboxaldehyde, n-dodecanal, heliotropin, α-hexylcinnamaldehyde, hydroxycitronellal, methylnonyl acetaldehyde, p-tert.butyl-α-methyl-dihydro-cinnamaldehyde (e.g. Lilial® Givaudan), n-undecen-10-al. 
     Ketones, such as acetylcedrene, allylionone, p-hydroxybenzyl-acetone, α-ionone, 2,4,4,7-tetramethyl-6,8-nonadien-3-one, p-methylacetophenone, methylionone, 1,2,3,4-tetrahydro-1,1-dimethyl-4-propionylnaphthalene. 
     Esters, such as ethyl acetoacetate, 3-ethyl-1,1-dimethyl-cyclohex-3-ene-2-carboxylic acid ethyl ester (Givescone™ Givaudan), 3-ethyl-1,1,4-trimethyl-cyclohex-3-ene-2-carboxylic acid ethyl ester (Myrascone™ Givaudan), allyl phenoxyacetate, amyl salicylate, benzyl acetate, benzyl salicylate, bornyl acetate, cedryl acetate, cinnamyl formate, cis-3-hexenyl acetate, cis-3-hexenyl benzoate, geranyl acetate, hexyl salicylate, isobutyl salicylate, linalyl acetate, linalyl anthranilate, methyl dihydrojasmonate, 4-[4-methyl-3-pentenyl]-cyclohex-3-en-1-yl-carbinyl acetate (e.g. Myraldylacetat™ Givaudan), oxyoctalin formate Giv. (Δ 1  -1,5,9,10-tetramethyl-5-formoxy-octalin), phenylethyl acetate, styrallyl acetate, terpenyl acetate, p-tert.butylcyclohexyl acetate. 
     Lactones, such as coumarin, γ-decalactone, γ-dodecalactone, γ-nonalactone, γ-undecalactone. 
     Various additional components often used in perfumery, such as acetaldehyde-propylphenyl-ethyl acetal, cyclocitrylideneacetonitrile, 1,1-dimethyl-4-acetyl-6-tert.butylindane, dodecahydro-3a,6-6-9a-tetramethyl(2,1-b)furan, eugenol, Galaxolid® IFF (7-acetal-1,1,3,4,4,6-hexamethyltetralin), indole, isobutylquinoline, p-menthane-8-thiol-3-one, methyleugenol, methyl 1 methyl-cyclododecyl ether (e.g. Madrox™ Givaudan), musk compounds (musk ketone, 12-oxahexadecanolide (e.g. Musk 174™ Naarden), 8,12-oxido-13,14,15,16-tetranorlabdane (Fixateur 404™). 
     The compounds of formula I can be used in wide limits which can extend in compositions, for example, from 0.01 (detergents)-50% (alcoholic solutions). It will be appreciated, however, that these values are not limiting values, as the experienced perfumer can also achieve effects with even lower concentrations or can synthesize novel complexes with even higher amounts. The preferred concentrations range between 0.05 and 10%. The compositions manufactured with I can be used for all kinds of perfumed consumer goods (eau de cologne, eau de toilette, extracts, lotions, creams, shampoos, soaps, salves, powders, deodorants, detergents, tobacco, etc.). 
    
    
     The compounds I can accordingly be used in the manufacture of compositions and, as will be evident from the above compilation, a wide range of known odorant substances can be used. In the manufacture of such compositions the known odorant substances enumerated above can be used according to methods known to the perfumer, such as e.g. from W. A. Poucher, Perfumes, Cosmetics and Soaps 2, 7th Edition, Chapman and Hall, London, 1974. 
     EXAMPLE 1 
     (a) 100 g of hydroxylamine hydrochloride are dissolved in 1 liter of ethanol and 100 g of pyridine in a round flask which is provided with a stirrer, a thermometer and a condenser. The mixture is stirred at room temperature for a quarter of an hour and 100 g of the ketone II, R═H, namely 2,2,4-trimethyl-1-phenyl-3-pentanone, are added to the solution. The reaction mixture is held at reflux temperature for 2 hours. Thereupon, the majority of the ethanol, namely about 3/4, is distilled off. After cooling the residue is poured on to ice-water and taken up in ether. The ethereal solution is washed as follows: firstly with water, thereupon with 5% dilute hydrochloric acid in order to eliminate the excess pyridine and then again with water until neutral. After evaporation of the ether there are obtained 99 g of the crude oxime I (with R═H) which still contain 77 g of unreacted ketone. This ketone (b.p. 90° C./1.5 mmHg) is distilled off. 
     The residue now consists of the crude oxime. 
     IR spectrum: typical bands at 3250 cm -1  (broad), 1660 cm -1  (moderately strong), 930 cm -1  (strong). 
     NMR: (60 MHz, CDCl 3 ) δ=9.7 (broad). 
     This crude oxime can be used in perfumery e.g. in the form of a 10%, or even a 1%, solution in isopropyl myristate. 
     (b) When 2,4,4-trimethyl-5-phenyl-3-hexanone is used as the starting material in the above process there is obtained 2,4,4-trimethyl-5-phenyl-3-hexanone oxime; 
     IR spectrum; typical bands at 3250 cm -1  (broad), 1650 cm -1  (weak), 935 cm -1  (strong). 
     NMR: (60 MHz, CDCl 3 ) δ=9.2 (broad). 
     (c) When 2,4,4-trimethyl-5-phenyl-3-heptanone is used as the starting material in the above process there is obtained 2,4,4-trimethyl-5-phenyl-3-heptanone oxide; 
     IR spectrum: typical bands at 3300 cm -1  (broad), 1650 cm -1  (weak), 940 cm -1  (strong). 
     The 2,4,4-trimethyl-5-phenyl-3-heptanone is obtainable by alkylating diisopropyl ketone with 1-chloro-1-phenyl-propane; b.p.: 78°-79° C./0.2 mmHg. 
     IR spectrum: typical bands at 1705 cm -1  (strong). 
     EXAMPLE 2 
     A. Cologne composition 
     
         ______________________________________                                    
                    Parts by weight                                       
______________________________________                                    
Bergamot oil          80                                                  
2-Ethyl-3,6,6-trimethyl-2-cyclohexen-                                     
                      80                                                  
1-yl-carboxylic acid ethyl ester                                          
Galaxolide ® 50 (in ethyl phthalate)                                  
                      120                                                 
(1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-                                       
hexamethylcyclopenta-γ-2-benzo-                                     
pyran)IFF                                                                 
Hydroxycitronellal    60                                                  
Methyl 1-methylcyclododecyl ether                                         
                      60                                                  
Bornyl acetate        40                                                  
Musk ketone           40                                                  
Givescone  ™ Giv (2-ethyl-6,6-                                         
                      20                                                  
dimethyl-2-cyclohexane-1-carboxylic                                       
acid ethyl ester)                                                         
Petitgrain oil        20                                                  
Sandalore ® Giv (3-methyl-5-                                          
                      30                                                  
(2,2,3-trimethylcyclopent-3-en-1-                                         
yl)pentan-2-ol)                                                           
Tree moss absolute     5                                                  
                      395                                                 
______________________________________                                    
 
    
     By adding 50 parts by weight of a 10% solution of the--preferred--compound I (with R═H) the resulting cologne base becomes much more natural. The somewhat camphorous note of the bornyl acetate, which was observed previously, is enveloped by the addition of the oxime. At the same time, the sandal note of Sandalore® is further brought into prominence. The effect achieved with the addition of the oxime corresponds to the effect which would be achieved by adding a natural product. 
     B. When 50 parts by weight of a 1% solution of the compound I (R═CH 3 ) in isopropyl myristate is added to the cologne composition of Example 2, the resulting base becomes fresher and greener. The camphorous note is enveloped and the petitgrain oil comes into prominence, thereby the natural character of the resulting composition gains extraordinarily. 
     C. Spicy base 
     
         ______________________________________                                    
              Parts by weight                                             
______________________________________                                    
Benzyl acetate  100                                                       
Hydroxycitronellal                                                        
                100                                                       
Phenylethyl alcohol                                                       
                100                                                       
Amyl salicylate 100                                                       
Patchouli oil   80                                                        
Ylang-ylang oil 50                                                        
Eugenol         50                                                        
Linalyl acetate 60                                                        
Musk ketone     50                                                        
Cedryl acetate  30                                                        
Epoxycedrene    30                                                        
Acetylcedrene   30                                                        
Coumarin        30                                                        
Spearmint oil   15                                                        
Thyme oil       15                                                        
Lemon oil        5                                                        
Dipropylene glycol                                                        
                105                                                       
                950                                                       
______________________________________                                    
 
    
     The addition of 50 parts by weight of a 10% solution of 2,2,4-trimethyl-1-phenyl-3-pentanone oxime in isopropyl myristate confers more freshness and more life to the above base. The phenolic, somewhat medicinal, secondary odour disappears in favour of a minty, fresh, light note. The spicy note is sharper, dryer, more herby, with a nuance after blackcurrants. The base is especially suitable for masculine perfume.