Patent Publication Number: US-4579680-A

Title: Aliphatic nitriles

Description:
This is a continuation of application Ser. No. 413,446, filed Aug. 31, 1982, now abandoned. 
    
    
     This invention relates to substituted saturated aliphatic nitriles, more particularly to alpha- and beta-substituted nitriles which have been found to have value in perfume compositions. 
     Various substituted aliphatic nitriles have been known for some years, but hitherto their value as perfume components has not been appreciated. Our work has shown that certain of the alpha- and beta-substituted aliphatic nitriles, some of which are novel, have particular merit in perfumery compositions. 
     Accordingly, the present invention provides a perfume composition comprising perfume components and an organoleptically discernible amount of a nitrile of the formula: 
     
         CH.sub.3 (CH.sub.2).sub.n RCN 
    
     in which 
     R=--CHCH 3  -- or --CHCH 3  CH 2  -- and in which, when 
     R=--CHCH 3  --, n is an integer from 5-9 and when 
     R=--CHCH 3  CH 2  --, n is an integer from 4-8. 
     In addition, this invention provides certain novel substituted nitriles of particular value in perfume formulations, having the formula: 
     
         CH.sub.3 (CH.sub.2).sub.n CHCH.sub.3 CH.sub.2 CN 
    
     in which n is 6, 7 or 8. 
     The nitriles useful in perfume compositions provided by this invention have, in addition to their useful odour characteristics, good stability when used in perfume formulations which are to be used or stored in an aggressive environment, such as in soaps, disinfectants, laundry powders and other compositions in which active chemicals are present or which have to withstand the effects of daylight or heat. 
    
    
     The nitriles useful according to this invention may be prepared by various processes, but a convenient process for the preparation of the alpha-substituted nitriles is as follows: 
     Procedure A 
     A solution of the required methyl alkyl ketone (50 m mol) and tosylmethylisocyanide (12 g, 60 m mol) in dry diglyme (120 ml) was added over 15 minutes at 0° C. under nitrogen to a stirred solution of potassium t-butoxide (freshly prepared from potassium 4.3 g, 0.11 g atom) in dry t-butanol (100 ml) and diglyme (100 ml). When the addition was complete, the mixture was allowed to warm to room temperature then stirred for 2 hours and left to stand overnight. The resultant solution was poured into water (400 ml) and extracted with light petroleum (3×100 ml, bp 40°-60° C.). The combined organic extracts were washed with water (2×500 ml), then brine (500 ml) and dried (MgSO 4 ). The solvent was removed under reduced pressure and the residue chromatographed using a column (3 cm diameter, 30 cm height) of silica gel with 5% ether in light petroleum (bp 40°-60°  C.) as solvent. Those fractions containing the product were freed of solvent under reduced pressure and the residue distilled to give the desired 2-methyl substituted nitrile. 
     A convenient process for the preparation of the betanitriles is as follows: 
     Procedure B 
     The required methyl alkyl ketone (1 mol), cyanoacetic acid (93.5 g, 1.1 mol), ammonium acetate (13 g, 0.17 mol) and toluene (175 ml) were stirred under reflux (pot temperature 140°-160° C.) in a Dean-Stark apparatus until carbon dioxide ceased to be evolved (3-6 hours). The resultant mixture was cooled, washed with saturated aqueous sodium hydrogen carbonate (2×50 ml) and water (50 ml) then the solvent was removed under reduced pressure. The crude mixture of nitriles was then added to one quarter of its volume of 50% aqueous sodium hydroxide to which Tergitol* (3 drops) had been added. The resulting mixture was stirred under reflux for 1 hour then cooled. The organic layer was removed, washed with water (3×50 ml) and distilled. 5% Palladium on carbon (0.1% by weight relative to the nitrile mixture) was then added followed by ethyl acetate (2×weight of distillate) and the suspension stirred vigorously in an atmosphere of hydrogen until uptake of gas ceased. The catalyst was removed by filtration and the solvent by evaporation under reduced pressure. Fractional distillation of the residue afforded the desired 3-methyl substituted nitrile. 
    
     The following table sets out the physical and the organoleptic properties of the nitriles useful in this invention: 
     
                                           TABLE                                   
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          Carbon                                                          
          Chain                                                           
Sample                                                                    
    Series                                                                
          Length                                                          
               Name        Structure                                      
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1   α-methyl                                                        
           8   2-methyloctanonitrile                                      
                           CH.sub.3 (CH.sub.2).sub.5 CHCH.sub.3 CH        
2   α-methyl                                                        
           9   2-methylnonanonitrile                                      
                           CH.sub.3 (CH.sub.2).sub.6 CHCH.sub.3 CN        
3   α-methyl                                                        
          10   2-methyldecanonitrile                                      
                           CH.sub.3 (CH.sub.2).sub.7 CHCH.sub.3 CN        
4   α-methyl                                                        
          11   2-methylundecanonitrile                                    
                           CH.sub.3 (CH.sub.2).sub.8 CHCH.sub.3 CN        
5   α-methyl                                                        
          12   2-methyldodecanonitrile                                    
                           CH.sub.3 (CH.sub.2).sub.9 CHCH.sub.3 CN        
6   β-methyl                                                         
           8   3-methyloctanonitrile                                      
                           CH.sub.3 (CH.sub.2).sub.4 CHCH.sub.3 CH.sub.2  
                           CN                                             
7   β-methyl                                                         
           9   3-methylnonanonitrile                                      
                           CH.sub.3 (CH.sub.2).sub.5 CHCH.sub.3 CH.sub.2  
                           CN                                             
8   β-methyl                                                         
          10   3-methyldecanonitrile                                      
                           CH.sub.3 (CH.sub.2).sub.6 CHCH.sub.3 CH.sub.2  
                           CN                                             
9   β-methyl                                                         
          11   3-methylundecanonitrile                                    
                           CH.sub.3 (CH.sub.2).sub.7 CHCH.sub.3 CH.sub.2  
                           CN                                             
methyleta.                                                                
    12    3-methyldodecanonitrile                                         
               CH.sub.3 (CH.sub.2).sub.8 CHCH.sub.3 CH.sub.2 CN           
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                Boiling Point                                             
Sample                                                                    
    Preparation (lit. bp)  Odour Description                              
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1   Procedure A, 76% yield                                                
                78-80°  C. at 8 m bar                              
                           Floral jasminic character                      
    from 2-octanone                                                       
                (85 at 10 mm Hg)                                          
                           with some celery aspects and                   
                           a hint of coconut/lactone -                    
                           very diffusive.                                
2   Procedure A, 69% yield                                                
                72-73° C. at 3 m bar                               
                           Soft, floral, lactonic,                        
    from 2-nonanone                                                       
                (100 at 10 mm Hg)                                         
                           jasmine/peachy character.                      
3   Procedure A, 77% yield                                                
                85-87° C. at 3 m bar                               
                           A fine, light, jasmine/floral                  
    from 2-decanone                                                       
                (115 at 10 mm Hg)                                         
                           character with a soft peach                    
                           quality.                                       
4   Procedure A, 74% yield                                                
                84° C. at 1 m bar                                  
                           Fresh, floral with some lilac                  
    from 2-undecanone                                                     
                (133 at 12 mm Hg)                                         
                           character - tenacious.                         
5   Procedure A, 59% yield                                                
                125-127° C. at 7 m bar                             
                           Soft, floral with a green                      
    from 2-dodecanone                                                     
                (146 at 10 mm Hg)                                         
                           jasminic type odour - very                     
                           persistent.                                    
6   Procedure B, 59%                                                      
                66-68° C. at 4 m bar                               
                           An unusual floral type                         
    yield from  (207-8 at 760 mm Hg)                                      
                           consisting of a distinct                       
    2-heptanone            fatty jasminic character                       
                           combined with an agrumen                       
                           quality.                                       
7   Procedure B, 16%                                                      
                93° C. at 8 m bar                                  
                           Fresh, jasminic floral type                    
    yield from  (95-6 at 2-3 mm Hg)                                       
                           with a slightly green                          
    2-octanone             quality.                                       
8   Procedure B, 49%                                                      
                72-74° C. at 0.7 m bar                             
                           Soft, citrus floral -                          
    yield from             reminiscent of jasmine.                        
    2-nonanone                                                            
9   Procedure B, 35%                                                      
                99-100° C. at 3 m bar                              
                           Light, fresh, green, floral                    
    yield from             suggesting lilac, with slight                  
    2-decanone             citrus undertones.                             
10  Procedure B, 26%                                                      
                95-97° C. at 0.7 m bar                             
                           Distinct orange character                      
    yield from             which is suffused by a light                   
    2-undecanone           green sea-fresh quality.                       
__________________________________________________________________________
 
    
     The following are two examples of perfume compositions comprising the nitriles of this invention: 
     
         ______________________________________                                    
Formula 1                                                                 
______________________________________                                    
Phenylethyl Alcohol    30.5                                               
Terpineol              6.0                                                
Paratertiary butyl cyclohexyl acetate                                     
                       15.0                                               
high cis (PPL)                                                            
Benzyl Salicylate      14.8                                               
Cinnamic Alcohol       10.0                                               
Sandalone (PPL)        5.0                                                
Galaxolide (IFF)       3.0                                                
Hexyl Cinnamic Aldehyde                                                   
                       10.0                                               
Coumarin               2.0                                                
Rose Base AB 380 (PPL) 2.0                                                
Isoeugenol             0.1                                                
Vetivert Brazilian     0.1                                                
Nitrile No 3           1.5                                                
______________________________________                                    
 
    
     Formula 1 in the absence of nitrile 3 has a floral, woody bouquet suitable for a toilet soap. The addition of 1.5% of nitrile 3 enhances the overall freshness, giving a light floral, fruity effect. Using the above formulation but substituting nitrile 9 in place of nitrile 3, a perfume is created having an added fresh lightness with an enhanced floral, fruity and citrus character. 
     The three novel nitriles provided by this invention are those numbered 8, 9 and 10 in the samples list and their mass spectral data are as follows. 
     
         ______________________________________                                    
Sample       Base Peak M1    M2   M3    M4   M5                           
______________________________________                                    
8     C.sub.10                                                            
             41        43:85 57:84                                        
                                  68:66 55:50                             
                                             96:46                        
9     C.sub.11                                                            
             41        57:85 43:84                                        
                                  68:56 55:50                             
                                             69:43                        
10    C.sub.12                                                            
             41        57:92 43:90                                        
                                  55:54 68:53                             
                                             70:48                        
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     Perfumes formulated using as an odorous component the nitriles provided by this invention may be employed in the various products, such as soaps, detergents, hairsprays, talcum powders and the like, which are normally augmented by the addition of a perfume.