Abstract:
Trimethylbicyclo [4.3.0] non-1-ene derivatives are fragrant substances which are suitable for use alone and in perfume and odorant compositions. Methods of preparation and representive compositions are also disclosed.

Description:
BACKGROUND OF THE INVENTION 
     The use of fragrances as perfumes and odorants has existed for as long as can be remembered. These substances were early obtained from suitable animal and plant sources, and since the nineteenth century synthetic fragrances have been prepared by chemists. 
     The requirements for a desirable fragrance are subjective and change with the fashion. This gives rise to a constant demand for new fragrances which may stand alone or act as compliments to those already available. 
     The problem faced by the synthetic chemist is the lack of predictability of success in producing an acceptable fragrance since it has yet to be established that there is any predictable relationship between chemical structure and fragrance characteristics or nuances. 
     U.S. Pat. No. 4,302,363 describes an isomer mixture of 4(5)-acetyl-7,7,9(7,9,9)-Trimethyl bicyclo[4.3.0]non-1-ene which is a valuable fragrance which has a warm ambergris odor. 
     OBJECT OF THE INVENTION 
     It is an object of the invention to provide a number of fragrant mixtures of isomer compounds. 
     Another object of the invention is to provide new fragrance mixtures having their own distinctive odor nuances. 
     It is a further object of the invention to provide perfume and odorant compositions containing the fragrant isomer mixtures of the invention. 
     Another object of the invention is to provide a method for the preparation of fragrant mixtures of isomer compounds. 
     A further object of the invention is to provide a fragrant mixture of three isomers of trimethylbicyclo[4.3.0]non-1-ene wherein the methyl groups are positioned in the respective isomers in the 7,9,9 7,7,9 and 6,8,8,-positions and is identified as 7,9,9(7,7,9/6,8,8)-trimethylbicyclo[4.3.0]non-1-ene. 
     These and other objects of the invention will become more apparent as the description thereof proceeds. 
     DESCRIPTION OF THE INVENTION 
     Now additional trimethylbicyclo[4.3.0]non-1-ene perfumes have been found which, too, are valuable perfumes with interesting and surprisingly different fragrance nuances. The new compounds are produced according to synthesis processes of organic chemistry known in themselves. As starting material one uses 2,2,4(2,4,4)-tri-methylcyclopentanone (I), which is always presents as an isomer mixture and is not obtainable as unitary compounds. This isomer mixture is transformed by Grignard reaction to the isomer mixture 1-vinyl-1-hydroxy-2,4,4 (and 2,4,4)-trimethylcyclopentane (II). Dehydration with p-toluene sulfonic acid gives 1-vinyl-2,4,4 (and 2,4,4)-trimethylcyclopent-1-ene (III), which consists of 3 isomers in each instance. The latter is transformed by Diels-Alder reaction with suitable dienophile aldehydes or ketones (compounds IV to IX) into corresponding trimethylbicyclo[4,3,0]non-1-ene derivatives of the invention which contain odorgenic acyl or aldehyde groups. 
     Suitable dienophile aldehydes or ketones, as used for the production of the compound of the invention, are selected from the group of consisting of acrolein, crotonaldehyde, ethylacrolein, pentene-3-one(2), emthyl-1-propenyl ketone and ethylvinyl ketone. 
     The odor nuances of the new compounds range between woody, green, sweet or respectively thujone, tobacco, coumarin, galbanum, spruce, ambergris scents and are outstanding for unusual lasting power. They can be mixed with other fragrances in the widest variety of proportions to produce new fragrance compositions. Generally the proportion in a fragrance composition ranges from between about 1 to 50 percent by weight, based on the total composition. Such compositions can be used to perfume cosmetic preparations, such as creams, lotions, colognes, aerosols, and toilet soaps, as well as in extract perfumery. But they may also be used for odor improvement of technical products such as washing and detergent products, softeners and textile treatment agents. For perfuming the various products, the compositions are generally added to them in concentrations of from 0.05 to 2 percent by weight, based on the total product. 
     The above described reaction process for the production of the new compounds can be represented by means of formulas as follows: ##STR1## a mixture of 3 isomers of ##STR2## This mixture is subjected to Diels-Alder reaction with single (i.e., one reaction) dienophiles selected from the group consisting of: 
     
         ______________________________________acrolein                (IV)crotonaldehyde          (V)ethylacrolein           (VI)pentene-3-one(2)        (VII)methyl isopropenyl ketone                   (VIII)ethyl vinyl ketone      (IX)to form: ##STR3## ##STR4## ##STR5##______________________________________ 
    
     wherein depending on the dienophile used R 1 , R 2 , R 3  and R 4  have the following meanings: 
     When the dienophile is: 
     acrolein: when R 1  and R 2  are H, R 3  and R 4  are different, being either H or CHO; and when R 3  and R 4  are H then R 1  and R 2  are different being either CHO or H. 
     crotanaldehyde: when R 1  and R 2  are different, being either CH 3  or H, then R 3  and R 4  are different being either CHO or H; and when R 3  and R 4  are different being either CH 3  or H then R 1  and R 2  are different, being either CHO or H, 
     ethylacrolein: when R 1  and R 2  are H, then R 3  and R 4  are different, being either CHO or C 2  H 5  ; and when R 3  and R 4  are H, then R 1  and R 2  are different being either CHO or C 2  H 5   
     pentene-3-one(2): when R 1  and R 2  are different, being either CH 3  or H, then R 3  and R 4  are different, being either CH 3  CO or H; and when R 3  and R 4  are different being either CH 3  or H, then R 1  and R 2  are different, being either CH 3  CO or H; 
     methyl isopropenyl ketone: when R 1  and R 2  are H, then R 3  and R 4  are different, being either CH 3  or CH 3  CO; and when R 3  and R 4  are H, then R 1  and R 2  are different, being either CH 3  or CH 3  CO 
     ethyl vinyl ketone: when R 1  and R 2  are H then R 3  and R 4  are different, being either C 2  H 5  CO or H; and when R 3  and R 4  are H, then R 1  and R 2  are different, being C 2  H 5  CO or H. 
     The new fragrances therefore are mixtures of 3 isomers in each instance, with acyl or respectively aldehyde groups and ring linkage (C 6  /C 7 ) being able to occupy axial or equatorial configuration. 
     The following examples are given by way of illustration and not by way of limitation. 
     GENERAL PROCEDURE FOR THE DIELS-ALDER SYNTHESIS 
     Heat 0.1 mole of diene (III) with 0.1 to 0.12 mole of dienophile compounds IV to IX while stirring for 4 to 9 hours with reflux or in an autoclave at 200° C. (in the case of methyl-isopropenyl ketone (VIII) under nitrogen at 100° C.). 
     After completed reaction, distill unreacted diene or dienophile and fractionate the Diels-Alder adduct under oil pump vacuum. 
    
    
     EXAMPLE 1 
     Three isomers 7,9,9(7,7,9/6,8,8)-trimethylbicyclo[4.3.0]-non-1-ene-4e/a(5e/a)-carbaldehyde 
     Reaction of (III) with acrolein in an autoclave, 4 hours at 200° C. B.p. 84°-88° C./0.6 mbar; GC: Isomer mixture. 
     IR (film): 2710, 1725/cm (CHO). 
     
         ______________________________________C.sub.13 H.sub.20 O        Calc.        Found______________________________________MG (GC/MS)   192.3        192    (Isomer)% C          80.1         81.2% H          10.5         10.4% O           8.3         9.5______________________________________ 
    
     Odor: woody, thujone, camphor nuances 
     EXAMPLE 2 
     Three isomers 7,9,9(7,7,9/6,8,8)-trimethylbicyclo[4.3.0]-non-1-ene-4e/a(5e/a)-methyl,4e/a(5e/a)-carbaldehyde 
     Reaction of (III) with crotonaldehyde in an autoclave, 6 hours at 200° C., B.p. 125°-135° C./18.6 mbar; isomer mixture. 
     IR (film): 2700, 1725/cm (CHO). 
     
         ______________________________________C.sub.14 H.sub.22 O        Calc.        Found______________________________________MG (GC/MS)   206.3        206    (Isomer)% C          81.5         81.4% H          10.75        10.90% O           7.75        7.79______________________________________ 
    
     Odor: woody, straw nuances. 
     EXAMPLE 3 
     Three isomers 7,9,9,(7,7,9/6,8,8)-trimethylbicyclo[4.3.0]-non-1-ene-4e/a-ethyl,4a/e-carbaldehyde(5e/a-ethyl,5a/e-carbaldehyde 
     Reaction of (III) with ethylacrolein in an autoclave, 6 hours at 200° C. 
     B.p. 105°-115° C./2 mbar: GC: isomer mixture. 
     IR (film): 2700, 1723/cm (CHO). 
     
         ______________________________________C.sub.15 H.sub.24 O        Calc.        Found______________________________________MG (GC/MS)   220.4        220    (Isomer)% C          81.76        80.90% H          10.98        10.60% O           7.26        8.30______________________________________ 
    
     Odor: Tobacco, coumarin nuances 
     EXAMPLE 4 
     Three isomers 4a/e(5a/e)-acetyl-5a/e(4a/e-methyl,7,9,9(7,9,9/6,8,8)-trimethylbicyclo[4.3.0]non-1-ene 
     Reaction of (III) with penten-3-one-(2) in an autoclave, 9 hours at 200° C. 
     B.p. 95°-105° C./2.4 mbar; GC: isomer mixture. 
     IR (film): 1710/cm (C═0); 1151/cm (COCH 3 ). 
     1350-1375/cm (mixed di-methyl, COCH 3 ). 
     
         ______________________________________C.sub.15 H.sub.24 O        Calc.        Found______________________________________MG (GC/MS)   220.4        220    (Isomer)% C          81.76        81.25% H          10.98        10.80% O           7.26        8.42______________________________________ 
    
     Odor: woody, sweet, ambergris, warm spruce, allylionone nuances. 
     EXAMPLE 5 
     Three isomers 4e/a(5e/a)-acetyl-4a/e(5a/e)-methyl,7,9,9(7,7,9/6,8,8)trimethylbicyclo[4.3.0]non-1-ene 
     Reaction of (III) with methylisopropenyl ketone at 100° C., 4 hours reflux (N 2  atmosphere). 
     B.p. 81°-87° C./0.3 mbar; GC: isomer mixture. 
     IR (film): 1708/cm (C═O); 1153/cm (COCH 3 ); 1350-1380 (mixed di-methyl, COCH 3 ); 3030, 810/cm (&gt;C═CH). 
     
         ______________________________________C.sub.15 H.sub.24 O        Calc.        Found______________________________________MG (GC/MS)   220.4        220    (Isomer)% C          81.76        81.80% H          10.98        11.00% O           7.26        7.30______________________________________ 
    
     Odor: Galbanum, dipentene nuances. 
     EXAMPLE 6 
     4e/a(5e/a)-Propionyl-7,9,9(7,7,9/6,8,8)-trimethylbicyclo[4.3.0]non-1-ene 
     Reaction of (III) with ethylvinyl ketone at 170° C., 2 hours reflux. 
     B.p. 105°-115° C./4 mbar: GC: isomer mixture. 
     IR (film): 1710/cm (C═0); 3020, 1340, 805 (&gt;C═CH). 
     
         ______________________________________C.sub.15 H.sub.24 O        Calc.        Found______________________________________MG (GC/MS)   220.4        220    (Isomer)% C          81.76        80.80% H          10.98        11.30% O           7.26        8.35______________________________________ 
    
     Odor: green, green bean pod nuances 
     EXAMPLE 7 
     Examples of composition 
     
         ______________________________________(a) Wood base:4e/a(5e/a-acetyl-4e/a(5a/e)-methyl,                 300    parts by weight7,7,9(7,9,9/6,8,8)-trimethylbicyclo[4.3.0] non-1-enevetiverylacetate      250    &#34;(Vetiveryl acetate)Sandela ® (Givaudan)                 150    &#34;Patchouliol (Patchouli oil)                 50     &#34;Ketonmoschus (Ketone musk)                 30     &#34;Eichenmoos Absolute   20     &#34;(Oakmoss Absolute)Labdanum Resin        10     &#34;Myrrhe Resin (Myrrh resin)                 5      &#34;Pfefferol (Pepper oil)                 5      &#34;Muskatnusol (Nutmeg oil)                 5      &#34;Cistusol (Cistus oil) 5      &#34;Eugenol               5      &#34;                 1000   parts by weight(b) Fern-like perfume7,9,9(7,7,9/6,8,8)-trimethylbicyclo[4.3.0]-                 50     parts by weightnon-1-ene-4e/a-ethyl, 4a/e-carbaldehyde(5e/a-ethyl,5a/3-carbaldehyde)Formaldehyde-cyclododecyl                 150    &#34;ethyl acetalBergamot oil          150    &#34;Methyl cyclo-octyl carbonate                 100    &#34;Methyl ionone         80     &#34;Lavandin oil          80     &#34;Citronellol           50     &#34;Citral                40     &#34;Musk ambrette         40     &#34;Oakmoss Absolute      40     &#34;Rosemary oil          30     &#34;Orange oil            30     &#34;Ilang-ilang oil       30     &#34;Vetiver oil           20     &#34;Lavandin Absolute     20     &#34;Benzyl isoeugenol     15     &#34;Cinnamon leaf oil     15     &#34;Coriander oil         15     &#34;Labdanum absolute     15     &#34;Eugenol               10     &#34;Patchouli oil         10     &#34;Thyme oil             10     &#34;                 1000   parts by weight______________________________________ 
    
     The preceding specific embodiments are illustrative of the practice of the invention. It is to be understood, however, that other expedients known to those skilled in the art or disclosed herein, may be employed without departing from the spirit of the invention or the scope of the appended claims.