New polycyclic Diels-Alder adducts which are formed on reaction of 8-vinyl-tricyclo-[5,2,1,0.sup.2,6 ]-dec-8-ene or 8-hydroxy-8-vinyl-tricyclo-[5,2,1,0.sup.2,6 ]-decane with alkenes or alkynes having one or two activating substituents, e.g., --COOH, --COOCH.sub.3, --COOC.sub.2 H.sub.5, --CHO, --COCH.sub.3, --COC.sub.2 H.sub.5 or --CN. They have green, fresh, fruity and in some cases woody odors with long-lasting tenacity and/or fixing properties. They can be used as constituents of perfumes and of compositions for perfuming body care products, detergents and other consumer products.

The present invention relates to Diels-Alder adducts of the general formula 
I 
##STR1## 
where R.sup.1 and R.sup.2 are --H or --CH.sub.3, or R.sup.1 and R.sup.2 
together are a further bond between the carbon atoms on which they are 
present, and X and Y are each --CH.sub.2 OH, --CH(OH)--CH.sub.3, --COOH, 
--COOCH.sub.3, --COOC.sub.2 H.sub.5, --CHO, --CO--CH.sub.3, --CO--C.sub.2 
H.sub.5 or --CN, or X and Y together are --CO--O--CO--, or one of X or Y 
is --H or CH.sub.3 and the other has one of the above meanings. 
The new polycyclic Diels-Alder adducts are distinguished by valuable scent 
characteristics. They have green, fresh, fruity and in some cases woody 
odors with long-lasting tenacity and/or fixing properties. They may be 
used as constituents of perfumes and of compositions for perfuming body 
care products, e.g. soaps, shampoos and hair lotions, detergents and other 
consumer products. Furthermore, they may be used for flavoring foodstuffs 
and tobacco. 
The present invention further relates to a process for the manufacture of 
the new compounds of the formula I, wherein the new 
8-vinyltricyclo-[5,2,1,0.sup.2,6 ]-dec-8-ene of the formula II 
##STR2## 
is subjected to a Diels-Alder reaction, by conventional methods, with a 
dienophile of the general formula III 
##STR3## 
where R.sup.1 and R.sup.2 are --H or --CH.sub.3 or R.sup.1 and R.sup.2 
together are a further bond between the carbon atoms on which they are 
present and X and Y are each --COOH, --COOCH.sub.3, --COOC.sub.2 H.sub.5, 
--CHO, --COCH.sub.3, --COC.sub.2 H.sub.5 or --CN, or X and Y together are 
--CO--O--CO--, or one of X and Y is --H or --CH.sub.3 and the other has 
one of the above meanings. 
The new Diels-Alder adducts of the formula I, in which R.sup.1 and R.sup.2 
are --H or --CH.sub.3 and one of X or Y is --CH.sub.2 OH or 
--CH(OH)--CH.sub.3 and the other is H, are obtained by reducing the 
corresponding oxo compounds by conventional methods. 
8-Vinyl-tricyclo-[5,2,1,0.sup.2,6 ]-dec-8-ene, required as a starting 
compound, can be manufactured by a simple conventional method, by 
elimination of water from 8-vinyl-tricyclo-[5,2,1,0.sup.2,6 ]-decan-8-ol, 
which in turn can be obtained by reacting tricyclo-[5,2,1,0.sup.2,6 
]-decan-8-one, which is readily accessible, with a vinyl-magnesium halide 
by the Grignard method. Instead of the diene II, 
8-vinyl-tricyclo-[5,2,1,0.sup.2,6 ]-decan-8-ol can be used as the starting 
material, but this requires more severe reaction conditions, e.g. higher 
temperatures and/or acid catalysts, and the yields are therefore 
frequently less. 
Suitable dienophiles of the formula III are: 
(a) Alkenes having only one activating substituent, i.e. compounds of the 
formula III, where R.sup.1 and R.sup.2 are --H or --CH.sub.3, one of X or 
Y is --COOH, --COOCH.sub.3, --COOC.sub.2 H.sub.5, --CHO, --CO--CH.sub.3, 
--CO--C.sub.2 H.sub.5 or --CN and the other X or Y is --H, i.e. 
mono-.alpha.,.beta.-unsaturated aldehydes, ketones, nitriles, carboxylic 
acids or carboxylic acid esters. Examples which may be mentioned are 
acrolein, methacrolein, crotonaldehyde, methyl vinyl ketone, 
pent-2-en-4-one, acrylonitrile, methacrylonitrile, crotononitrile, acrylic 
acid, methacrylic acid, crotonic acid and the methyl esters and ethyl 
esters of the said 3 acids. The above aldehydes, ketones and nitriles are 
preferred. 
(b) Alkenes with two activating substituents, i.e. compounds of the formula 
III, where R.sup.1 and R.sup.2 are --H or --CH.sub.3, especially --H, and 
X and Y are each --COOH, --COOCH.sub.3, --COOC.sub.2 H.sub.5, --CHO, 
--CO--CH.sub.3, --CO--C.sub.2 H.sub.5 or --CN, or X and Y together are 
--CO--O--CO--. Examples which may be mentioned are dimethyl fumarate, 
diethyl fumarate and maleic anhydride. 
(c) Alkylenes with only one activating substituent, i.e. compounds of the 
formula III, where R.sup.1 and R.sup.2 together are a further bond between 
the carbon atoms on which they are present, one of X or Y is --COOH, 
--COOCH.sub.3, --COOC.sub.2 H.sub.5, --CHO, --CO--CH.sub.3, --CO--C.sub.2 
H.sub.5 or --CN and the other is --H or --CH.sub.3. Examples which may be 
mentioned are propionaldehyde (propynal), butyn-2-al, propionic acid, 
tetrolic acid (butyn-2-oic acid), and the methyl esters and ethyl esters 
of the said acids. 
(d) Alkynes with two activating substituents, i.e. compounds of the formula 
III, where R.sup.1 and R.sup.2 together are a further bond between the 
carbon atoms on which they are present and X and Y are each --COOH, 
--COOCH.sub.3, --COOC.sub.2 H.sub.5, --CHO, --CO--CH.sub.3, --CO--C.sub.2 
H.sub.5 or --CN. Examples which may be mentioned are acetylenedicarboxylic 
acid and its methyl and ethyl esters. 
The dienophiles of the formula III are, in general, known and commercial 
compounds. 
Preferably, the alkenes with only one actuating substituent, described 
under (a), are used as dienophiles of the formula III. 
In general, the Diels-Alder reaction is carried out by bringing a mixture 
of 8-vinyl-tricyclo-[5,2,1,0.sup.2,6 ]-dec-8-ene (II), the dienophile of 
the formula III and, if appropriate, an inert solvent, to from 0 to 
150.degree. C., preferably from 30 to 80.degree. C., for the length of the 
reaction time. The latter is from about 1 to 200 hours, depending on the 
nature of the dienophile. The dienophile is in general used in from about 
0.5 to 10 molar amount, preferably in from about 2 to 5 molar amount, 
based on II. 
To avoid possible resinification reactions, a small amount, i.e. from about 
10 to 100 mg per mole of II, of a conventional stabilizer for Diels-Alder 
reactions, e.g. hydroquinone, is generally added to the reaction mixture. 
The reaction may be carried out in the absence of solvents or in an inert 
solvent. 
Examples of inert solvents which can be used are aliphatic hydrocarbons, 
e.g. pentane, hexane, cyclohexane and hydrocarbon fractions, aromatic 
hydrocarbons, e.g. benzene, toluene or xylene, chlorohydrocarbons, e.g. 
methylene chloride, chloroform or chlorobenzene, ethers, e.g. diethyl 
ether, dipropyl ether, diisopropyl ether, tetrahydrofuran and anisole, 
alcohols, e.g. methanol, ethanol, propanol, isopropanol and cyclohexanol, 
ketones, e.g. acetone, methyl ethyl ketone and methyl isopropyl ketone, 
amides, e.g. dimethylformamide, dimethylacetamide and 
hexamethylphosphotriamide or nitro compounds, e.g. nitromethane and 
nitrobenzene, or mixtures of the said solvents. 
The reaction is either carried out at atmospheric pressure or under the 
autogenic pressure of the reactants in closed reaction vessels. 
The reaction mixture is worked up by conventional methods, e.g. by 
distillation. 
Regarding further details of Diels-Alder reactions, reference may be made 
to R. Sauer, Angew. Chem. 79 (1967), 77-94. 
The Diels-Alder adducts are in general obtained as mixtures of different 
isomers. When using unsymmetrical olefins of the formula III, 8 
stereoisomeric Diels-Alder adducts are possible, depending on the steric 
course of the addition reaction. The dienophile can attack "meta" or 
"ortho" to the C.sub.9 of the diene of the formula II, "exo" or "endo" and 
from above or from below. The general rules of the Diels-Alder reaction 
and analogous examples with vinyl cyclohexenes or vinyl-bicylenes (see A. 
S. Onishchenko "Diene Synthesis", Israel Program for Scientific 
Translation, Jerusalem 1964, pages 410-445, especially pages 410-413 and 
pages 423-425) lead to the expectation that the main product would be the 
"ortho-endo" isomer, i.e. in the case of acrolein the isomers 
##STR4## 
with the attack "from below" in the former case and "from above" in the 
latter. A prediction of the actual attack is difficult, given the 
complicated stereochemistry of the diene, and is decisively dependent on 
the exo/endo configuration of the 5-membered ring. If symmetrical olefins 
and alkynes are used as dienophiles of the formula III, the number of 
possible stereoisomers is less. 
The stereoselectivity of the reaction can be increased by using very low 
reaction temperatures and/or by adding catalytic amounts of Lewis acids, 
e.g. BF.sub.3, AlCl.sub.3, ZnCl.sub.2 and the like (l.c., especially page 
84). 
If the reaction is carried out in the presence of catalytic amounts of a 
Lewis acid such as AlCl.sub.3, BF.sub.3, SnCl.sub.4 or ZnCl.sub.2, the 
procedure followed is that described above, but at lower temperatures, 
i.e. at from about -80 to +20.degree. C., preferably from -40 to 0.degree. 
C. The amount of catalyst is from 0.1 to 10%, preferably from 0.5 to 5%, 
based on II employed. 
Carbonyl compounds can be reduced to the alcohols in accordance with 
numerous standard processes, e.g. by catalytic hydrogenation, by reduction 
with metals or metal hydrides or by electrochemical or photochemical 
reduction. Regarding further details, reference may be made to S. Patai, 
"The Chemistry of the Hydroxyl Group", Interscience Publishers 1971, pages 
231-243. Example 3 describes the reduction of a carbonyl compound with a 
metal hydride (NaBH.sub.4). 
The new polycyclic Diels-Alder adducts are distinguished by valuable scent 
properties. They have green, fresh, fruity and in some cases woody scents 
with long-lasting tenacity. Furthermore, they possess fixing properties. 
Accordingly, they can be used as constituents of perfumes and of 
compositions for perfuming body care products, e.g. soaps, shampoos and 
hair lotions, detergents and other consumer products. The scent depends 
somewhat on the stereochemistry (exo/endo ratio) of the 
tricyclo-[5,2,1,0.sup.2,6 ]-decan-8-one employed, but in general it is 
satisfactory to use the adducts obtained from the commercial ketone.

EXAMPLE 
A solution of 8.0 g (0.05 mole) of 8-vinyl-tricyclo-[5,2,1,0.sup.2,6 
]-dec-8-ene, 10.6 g (0.2 mole) of acrylonitrile, 50 ml of toluene and 10 
mg of hydroquinone is heated at 80.degree. C. for 12 hours. The reaction 
mixture is then cooled, washed with twice 30 ml of water, concentrated and 
distilled. 8.1 g (corresponding to 76% of theory) of an 80 : 20 mixture of 
nitriles pass over at from 125 to 128.degree. C./0.2 mm Hg. From the 
analytical and spectroscopic data, the main product probably has the 
formula I, where R.sup.1, R.sup.2 and Y are --H and X is --CN. 
n.sub.D.sup.25 : 1.5325. 
Scent: fresh, flowery, slightly fruity (lime), good tenacity.