Abstract:
Oderiferous compositions containing certain novel 1,1-dialkyl naphthopyrans are disclosed. The 1,1-dialkyl naphthopyrans involved have the formula ##SPC1## 
     Wherein R 1  and R 2  each represent a lower alkyl group having from 1 to 4 carbon atoms and the dotted lines indicate an optional double bond emanating from the carbon atom in the 4a position, and mixtures thereof. R 1  and R 2  preferably both represent methyl. 
     Processess for the production of said 1,1-dialkyl naphthopyrans are also disclosed.

Description:
RELATED APPLICATIONS 
     This is a division of application Ser. No. 328,928, filed Feb. 2, 1973 now U.S. Pat. No. 3,901,924. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention relates to perfumes and odoriferous products containing certain naphthopyrans. 
     According to the present invention there are provided perfumes and odoriferous products containing naphthopyrans having the general formula: ##SPC2## 
     Wherein R 1  and R 2  each represent a lower alkyl group having from 1 to 4 carbon atoms and the dotted lines indicate an optional double bond emanating from the carbon atom in the 4a position, and mixtures thereof. R 1  and R 2  preferably both represent methyl. 
     The naphthopyrans utilized according to the invention may be prepared by condensing 2-hydroxyethyl-2-hydroxy-decalin having the formula: ##SPC3## 
     With a di-lower alkyl ketone having the formula: ##EQU1## wherein R 1  and R 2  have the meanings given above, and then if desired, subjecting the product to catalytic hydrogenation. 
     The ketone of formula III is preferably acetone, but other ketones such as methylethyl ketone, methylisobutyl ketone, ethylisobutyl ketone, methyl-n-propyl ketone or diethyl ketone may also be used. 
     The condensation is conveniently effected in a conventional manner using an acid catalyst. Examples of suitable acid catalysts include sulphuric acid, perchloric acid, p-toluenesulphonic acid and boron trifluoride etherate. 
     The condensation gives rise to a mixture of the isomers having the following formulae: ##SPC4## ##SPC5## 
     Wherein R 1  and R 2  have the meanings given above. 
     Under the reaction conditions employed herein, the compounds having the formulae IV and VII are formed in the largest yields and the compounds having the formulae V and VIII only in a small proportion. The individual isomers of the mixture of isomers can be separated from each other and isolated in pure form by conventional processes such as for example by chromatography. 
     The starting material of formula II may conveniently be prepared by reducing a corresponding ester having the formula: ##SPC6## 
     Wherein R represents an alkyl group having from 1 to 6 carbon atoms. The reduction may conveniently be effected by conventional methods for example by treatment with sodium in a suitable solvent such as anhydrous ethanol or with diisobutyl aluminium hydride. 
     The catalytic hydrogenation of the mixture of the isomers IV to IX to obtain the saturated compounds of formulae: ##SPC7## 
     May be effected by conventional methods such as for example using platinum or palladium on carbon or Raney nickel, as the catalyst. 
     The starting material having the formula X may convenently be prepared by treating a mixture of cis and trans β-decalones with an α-halo ester having the formula: X--CH 2  COOR wherein X represents a halogen atom, preferably bromine, and R represents an alkyl group having from 1 to 6 carbon atoms, in the presence of zinc. The progress of the reaction can be assisted by addition of a small quantity of activator for the zinc. Examples of suitable activators include iodine, mercuric chloride, mercuric bromide and copper. The group R is preferably methyl or ethyl. 
     The compounds of formula I have remarkable odors which are in general reminiscent of the odor of ambergris. They are hence useful in the preparation of odoriferous compositions. They may be used in the preparation of perfumes as well as for perfuming commercial products such as toilet waters, cosmetics, soaps, washing liquids and other products. The quantity in which the compounds according to the invention may be used varies widely, depending on the nature of the product and the desired odour intensity. In the preparation of concentrates, the naphthopyrans may for example conveniently be used in a proportion of from 1 to 15% by weight. For the preparation of perfumes of the floral type the compounds may be used in a proportion of 1 to 5% by weight, and for perfumes of the &#34;chypre&#34; type in a proportion of from 5 to 10% by weight. A proportion of from 5 to 10% by weight is also an appropriate proportion for the preparation of concentrates utilisable for perfuming soaps. In certain applications concentrations of 1 to 5% by weight of the compounds of formula I, may be used. 
    
    
     The invention will now be illustrated with reference the following Examples. 
     EXAMPLE 1 
     94 g Of 2-hydroxyethyl-2-hydroxy-decalin are dissolved in 1500 ml of acetone; 30 ml of concentrated sulphuric acid are added thereto and the solution is left for seven hours at ambient temperature. The solution is then neutralised with 1000 ml of a 9% aqueous solution of sodium bicarbonate, extracted with benzene and washed to neutrality thereby giving 70 g of crude product which are rectified. There are thus obtained 45 g of a mixture of decahydro-1,1-dimethyl-1H-naphtho-[2,3-c]pyrans and decahydro-1,1-dimethyl-1H-naphtho [1,2-c]pyrans having the formulae IV to IX given above. This represents a yield of about 40%. The product has b.p. 1 .0 = 88°-90°C and n D   20  = 1.5110. 
     The starting material may be prepared as follows: 
     a. To 112 g of powdered electrolytic zinc which is covered by benzene and to which has been added some crystals of mercuric chloride there is added dropwise several ml of a solution composed of the following mixture: 228 g of β-decalone, 228 g of ethyl bromoacetate and 450 ml of anhydrous benzene. The mixture is then refluxed to initiate the reaction; once the reaction has started heating is stopped and the rest of the solution is added so as to maintain reflux. After the addition is completed, refluxing is continued for a further two hours. After cooling, the mass is hydrolysed with 850 ml of a 10% aqueous solution of sulphuric acid. The mass is then extracted with benzene, the benzene solutions washed to neutrality, the benzene distilled and 330 g of crude product are obtained which are rectified under 0.5 mm and which yields 310 g of pure 2-carbethoxy-methyl-2-hydroxy-decalin. Yield = 86%, b.p. 0 .5 = 112°-115°C; n D   15  = 1.4863. 
     b 1 . 86.25 g Of small pieces of sodium are added to 60 g of 2-carbethoxy-methyl-2-hydroxy-decalin and 900 ml of anhydrous ethyl alcohol. A vigorous reaction sets in which causes the reaction medium to reflux. Reflux is maintained for 1 hour. The mass is cooled, 1000 ml of water added, the alcohol distilled off and the residue is taken up in a little warm water. After cooling the mass is extracted three times with 250 ml of diethyl ether. The ethereal solutions are washed to neutrality and distilled; there are thus obtained 40 g of crude product which are rectified under 0.5 mm. This rectification gives 22 g of 2-hydroxyethyl-2-hydroxy-decalin (b.p. 0 .5 = 138°-140°C), which represents a conversion of about 42%. 
     b 2 . A solution of 235 g of diisobutyl aluminium hydride in 300 ml of anhydrous benzene is added dropwise to a mixture of 120 g of 2-carbethoxymethyl-2-hydroxy-decalin and 120 ml of anhydrous benzene under nitrogen. During the addition the temperature of the reaction mass is held between 15° and 20°C. This temperature is maintained for a further two hours after the end of the addition. The mass is then cooled to 0°C and hydrolysed with 1500 ml of a 10% aqueous solution of sulphuric acid. The temperature is allowed to return to ambient, the organic layer decanted and the mother liquor extracted twice with 250 ml of benzene. The benzene extracts are then combined and washed to neutrality. After distillation of the solvent on a water bath under reduced pressure the crude product is rectified giving 72 g of 2-hydroxy-ethyl-2-hydroxy-decalin (72% yield) having b.p. 1  = 147°. 
     EXAMPLE 2 
     110 g Of decahydrodimethylnaphthopyran prepared as described in Example 1, is introduced into a 250 ml autoclave followed by 50 ml of absolute ethyl alcohol and 3.3 g of 5% palladium on carbon. Hydrogen is then introduced under a pressure of 80 kg/cm 2 . After eight hours at 120°C the hydrogenation is stopped. After cooling and filtration of the catalyst the alcohol is distilled off under reduced pressure and 100 g of crude product are obtained which are rectified. There are thus obtained 90 g of a product (80% yield) having the following constants: b.p. 0 .5 = 95°-96°C; n D   15  = 1.5010 and being a mixture of perhydro-1,1-dimethyl-naphtho[2,3-c]-pyran and perhydro-1,1-dimethyl-naphtho[1,2-c]-pyran. 
     The use of the compound in accordance with the present invention as odoriferous agents is illustrated in the following Examples A to E. 
     
         ______________________________________Example A    Concentrate for perfume______________________________________40       Ylang Extra oil120      Bergamet Peel oil Extra50       Benzyl acetate80       Phenylethyl alcohol220      Methylionone20       Florentine iris absolute20       Galbanum oil20       Phenylacetic aldehyde, 50% in ethyl phthalate20       C.11 aldehyde (100%), 10% in ethyl phthalate20       Rose of May absolute80       Jasmin absolute70       Benzyl salicylate60       Dioxa-2,7-cycloheptadecanone, 50% in ethyl    phthalate80       Vetiveryl acetate100      Mixture of the isomers of the aforesaid    formulae IV to IX1000______________________________________ 
    
     
         Example B    Concentrate for perfume (Chypre type)______________________________________10       Benzyl acetate20       Artemisia oil30       Bergamot Zest Peel oil Extra35       Lemon Peel oil Extra40       Linalol50       Lavender oil Laragne 50%15       Neroli oil40       Ylang Ylang oil Nossi Be20       Rose of May absolute20       C.19 aldehyde (100%), 10% in ethyl phthalate30       C.11 aldehyde (100%), 10% in ethyl phthalate50       α-Amylcinnamicaldehyde20       Coriander oil2        Galbanum oil10       Geranium Bourbon oil20       Geraniol100      Hydroxycitronnellal100      Jasmin absolute10       Oak Moss absolute30       Forest moss absolute30       Sandalwood oil East Indies20       Methylionone20       Patchouli oil Grasse8        Isobutylquinoline10       Amyl salicylate20       Benzyl salicylate10       Styrax oil20       Vetiver oil Bourbon20       Coumarin30       Dioxa-2,7-cycloheptadecanone, 50% in ethyl    phthalate10       C.16 aldehyde (100%), 10% in ethyl    phthalate60       Musk Ambrette20       Musk ketone70       Mixture of the isomers of the aforesaid    formulae IV to IX1000______________________________________ 
    
     
         Example C    Toilet water______________________________________180      Bergamot Peel oil Extra260      Lemon Peel oil Extra20       Bornyl acetate30       Scotch Pine oil40       Linalol20       Geranium Bourbon oil100      Lavender oil Laragne20       Artemisia oil120      Hydroxycitronellal20       Methylionone10       Eugenol Extra60       Benzyl salicylate60       Sage Clary oil Grasse20       Musk ketone40       Mixture of the isomers of the aforesaid    formulae IV to IX1000______________________________________ 
    
     
         Example D    Perfume (Chypre)______________________________________50       Benzyl acetate50       Linalyl acetate100      Lemon Peel oil Extra20       Coriander oil5        Neroli oil50       Ylang Ylang oil extra20       C.11 aldehyde, 10% in ethyl phthalate20       C.12 aldehyde, 5% in ethyl phthalate80       α-Hexylcinnamicaldehyde80       Jasmin absolute50       Rose of May absolute20       Citronellol60       Hydroxycitronellal40       Rose of the Orient oil10       Styrallyl acetate80       Caryophyllenyl acetate30       Forest moss absolute15       Coumarin80       γ-Methylionone10       Patchouli oil20       Civet absolute, 10% in ethyl phthalate20       Benzoin resinoid40       Dioxa-2,7-cycloheptadecanone50       Mixture of perhydro-1,1-dimethyl-naphtho-    [2,3-c]pyran and perhydro-1,1-dimethyl-naphtho[1,2-c]pyran1000______________________________________ 
    
     
         Example E    Perfume (Fougere)______________________________________30       Petitgrain oil Grass30       Linalol170      Bergamot Peel oil Extra280      Lemin Peel oil Extra40       Sage Clary Grasse20       Geranium Bourbon oil20       C.12 aldehyde, 5% in ethyl phthalate40       Forest moss absolute10       Vetiver Bourbon oil100      Hydroxycitronellal40       Sandalwood oil30       γ-Methylionone20       Dioxa-2,7-cycloheptadecanone70       Linalyl acetate100      Mixture of perhydro-1,1-dimethyl-naphtho    [2,3-]pyran and perhydro-1,1-dimethyl-naphtho[1,2-c]pyran, 50% in ethyl phthalate1000______________________________________