Perfume compositions containing 8 allyl-8-hydroxytricyclo [5,21,02.6 ]
This is a Division of application Ser. No. 826,768 filed Aug. 22, 1977 now U.S. Pat. No. 4,124,771 which in turn is a division of application Ser. No. 635,213 filed Nov. 25, 1975, now U.S. 4,057,516. 
    
    
     This invention relates to a process for the preparation of a starting material to be used in perfumery. More specifically the invention relates to a process for imparting an improved odor of castoreum to perfume compositions and perfumed materials. 
     In perfumery many natural materials are used. However, these materials suffer from the disadvantage of not always being available in sufficient quantities. Moveover they are often expensive and not of consistent quality. The use of certain animal materials also may be objected to because of the danger of extinction of the animal species under consideration, or because collection of the product is annoying to the animal. So it is advantageous to prepare or compound synthetic perfume materials whose odor properties approach those of the natural materials as closely as possible. Castoreum is an animal material derived from beavers (Castor fiber). It is very popular for use in perfumery but is expensive and hard to obtain for the reasons set forth above. 
     In all attempts to imitate the odor of castoreum, compounds were used that are known to be constituents of natural castoreum (see for example: E. Lederer, Odeurs et Parfums des Animaux in &#34;Fortschritte der Chemie organischer Naturstoffe&#34; VI (1949), p. 112). However, an additional amount of natural castoreum was always necessary to obtain a high quality castoreum odor in perfume compositions (see for example: F. Cole, &#34;Le Livre du Parfumeur&#34;, Casterman, Paris (1951), p. 421). 
     It was found that a very natural and satisfactory castoreum odor can be imparted to perfume compositions, without using any natural castoreum, by adding o-hydroxybenzyl ethyl ether of the formula ##STR1## and/or 8-allyl-8-hydroxytricyclo [5,2,1,0 2 ,6 ] decane of the formula ##STR2## to other components commonly used in preparing perfume compositions. 
     The phrase &#34;perfume composition&#34; is used to mean a mixture consisting of for example essential oils, hydrocarbons, alcohols, esters, acids, aldehydes, ketones and other odorous and non-odorous substances. This mixture may be used as such, or after dilution with a suitable solvent (e.g. alcohol) to impart a desired odor to products like detergents, soaps, creams, lotions and other cosmetics. 
     O-hydroxybenzyl ethyl ether is known but the odor description given in the literature does not give any indication about its usefulness in perfumery. The preparation of o-hydroxybenzyl ethyl ether is described in: R. Chromecek, Chem. Listy 49 (1955), 1831; J. de Jonge and B.H. Bibo, Rec. Trav. Chim. 74 (1955), 1448; J. Thiele and O. Dimroth, Ann. 305 (1899), 110. 
     The compound 8-allyl-8-hydroxytricyclo [5,2,1,0 2 ,6 ]decane is prepared in a way known per se, from tricyclo [5,2,1,0 2 ,6 ]decane-8-one and an allylmagnesium halogenide. Both stereo-isomeric ketones (endo and exo) will undergo this Grignard reaction and both will yield two new stereo-isomers because of the introduction of a new asymmetric center (indicated by *). It is possible to separate the four stereo-isomers by methods known per se, but this is not necessary for practicing the invention. So for economical reasons the use of the mixture of isomers is preferred. 
     Although the odors of o-hydroxybenzyl ethyl ether and 8-allyl-8-hydroxytricyclo [5,2,1,0 2 ,6 ] decane are very different, they are both clearly reminiscent of castoreum. The compounds may be used either separately or together in preparing a synthetic castoreum, if desired in conjunction with compounds known to be components of natural castoreum (e.g. benzoic acid, salicyclic acid, their methyl and ethyl esters, cresol and other phenolic compounds, acetophenone, etc.). The addition of o-hydroxybenzyl ethyl ether accentuates the phenolic character and improves the odor of a synthetic castoreum when used in an amount of 1000 ppm by weight or more. On the other hand 8-allyl-8-hydroxytricyclo [5,2,1,0 2 ,6 ] decane has a more sweet animal character and improves the odor of a synthetic castoreum when used in amounts of 100 ppm by weight or more. Especially the combination of o-hydroxybenzyl ethyl ether and 8-allyl-8-hydroxytricyclo[5,2,1,0 2 ,6 ] decane makes it possible to obtain a very near approach to the odor of natural castoreum. With this combination a synthetic castoreum may be prepared which is so close to nature that it is able to substitute natural castoreum in any desired application. It is also possible to use o-hydroxybenzyl ethyl ether and 8-allyl-8-hydroxytricyclo[5,2,1,0 2 ,6 ] decane either separately or in combination, directly in a perfume composition to impart a castoreum effect. 
     The weight ratio of o-hydroxybenzyl ethyl ether to 8-allyl-8-hydroxytricyclo [5,2,1,0 2 ,6 ] decane to be used depends on the desired effect. In general it will be between 300:1 and 1:5. Preferably a ratio between 30:1 and 1:1 is used. As far as the use in synthetic castoreum is concerned, one has to keep in mind the minimum effective amounts of both compounds as described above. When using such a synthetic castoreum in a perfume composition, the concentrations of o-hydroxybenzyl ethyl ether and 8-allyl-8-hydroxytricyclo [5,2,1,0 2 ,6 ] decane in the final composition may be much lower, depending on the amount of synthetic castoreum used in this composition. 
    
    
     The following examples are illustrative for the preparation of 8-allyl-8-hydroxytricyclo [5,2,1,0 2 ,6 ] decane and the use of o-hydroxybenzyl ethyl ether and 8-allyl-8-hydroxytricyclo[5,2,1,0 2 ,6 ] decane as perfume components. 
     Example 1 
     Preparation of 8-allyl-8-hydroxytricyclo [5,2,1,0 2 ,6 ] decane. 
     In a one litre reaction vessel, equipped with a stirrer, a cooler and a dropping funnel, 26.4 g magnesium, 100 g tetrahydrofurane and 1 g allyl chloride were heated to about 40° C. to start the reaction. A mixture of 76.5 g allyl chloride, 250 g tetrahydrofurane and 150 g tricyclo [5,2,1,0 2 ,6 ] decan-8-one was added in four hours, keeping the temperature at 35°-40° C. The reaction mixture was stirred for an additional 30 minutes and subsequently poured into a mixture of 600 g of ice and 80 g of acetic acid. The layers were separated and the water layer extracted twice with toluene. The combined organic layers were washed with 5% soda solution until alkaline and subsequently with water until neutral. The organic solvent was removed by distillation under reduced pressure. The residue was distilled on a Vigreux head at 2 mm.Hg. The fraction boiling between 93° and 95° C. was collected. 
     Yield: 80%, n D   20  : 1.5154. 
     EXAMPLE 2 
     A synthetic castoreum was prepared by mixing the following ingredients (amounts given in parts by weight): 
     
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738       benzoic acid                                                    
50        farnesol                                                        
20        farnesyl acetate                                                
10        farnesyl isobutyrate                                            
15        o-cresol                                                        
5         p-cresol                                                        
4         m-cresol                                                        
6         salicylic acid                                                  
2         borneol                                                         
1         eugenylphenyl acetate                                           
25        ethyl benzoate                                                  
10        methyl benzoate                                                 
6         methyl phenyl carbinol                                          
4         acetophenone                                                    
2         pentanoic acid                                                  
2         butanoic acid                                                   
900       This mixture was called mixture A.                              
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     The following mixtures were prepared: 
     
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Mixture B:                                                                
        900    parts by weight of mixture A                               
        85     parts by weight of o-hydroxybenzyl ethyl                   
               ether                                                      
        985    parts.                                                     
Mixture C:                                                                
        900    parts by weight of mixture A                               
        15     parts by weight of 8-allyl-8-hydroxytricyclo-              
               [5,2,1,0.sup.2,6 ] decane                                  
        915    parts.                                                     
Mixture D:                                                                
        900    parts by weight of mixture A.                              
        85     parts by weight of o-hydroxybenzyl ethyl                   
               ether                                                      
        15     parts by weight of 8-allyl-8-hydroxitricyclo-              
               [5,2,1,0.sup.2,6 ] decane                                  
        1000   parts.                                                     
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     The mixtures A, B, C and D were compared by 7 trained perfumers. B and C were unanimously preferred over A. Two experts preferred C over B, the others preferred B over C. However D was judged unanimously as the mixture with the best and most natural castoreum odor. 
     EXAMPLE 3 
     By mixing the following ingredients a men&#39;s cologne concentrate was prepared using the synthetic castoreum mixture D of Example 2 (amounts given in parts by weight): 
     
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15      musk-ketone                                                       
15      Musk R1® (11-oxa-hexadecanolide)                              
10      tonka absolute                                                    
10      heliotropine                                                      
20      benzylisoeugenol                                                  
15      mousse absolute                                                   
10      galbarum resin                                                    
15      benzoe resin Siam                                                 
75      lemon oil Italian                                                 
200     bergemot oil                                                      
10      verveic oil                                                       
100     sandalwood oil E.I.                                               
100     α-idomethylionone                                           
50      cedarwood oil Virginia                                            
25      clove bud oil                                                     
50      Rosana NB 131*                                                    
50      Jasmin NB 133*                                                    
50      vetiveryl acetate                                                 
25      yland ylang I                                                     
10      geranium oil Bourbon                                              
10      basil oil                                                         
10      angelica root oil                                                 
10      clary sage oil                                                    
50      lavender oil 45-47%                                               
30      lauric aldehyde, 10% in diethyl phthalate                         
10      civette absolute, 10% in ethanol                                  
25      mixture D of Example 2, 10% in benzylalcohol.                     
1000                                                                      
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 *perfume base of Naarden International.