1-Isopropenyl-spiro-decen- or -decan-8-ones - prepd by ring-closure of 3-isopropenyl-(3-keto-4-pentenyl)-1-cyclopentenes with Lewis acids useful as perfumes

摘要

Perfumes (I): (where R1 and R2 each is H or lower alkyl and 1 of the 3 dotted lines is an additional bond) are prepd. by ring-closure of a cyclopentene having the general formula (II) in an organic solvent in presence of a Lewis acid, pref. SnCl4 or TiCl4. (I) have a wooden, background note and are useful as modifiers, esp. in 0.1-10 wt.% concn., of existing perfume compsns.; in 0.001-0.1 wt.% concn. as perfumes for cosmetics, detergents, aerosols, soaps, creams or lotions, as starting materials for further perfumes. Pref. (I) are 1-isopropenyl-4-Me- and -4,8-di-methyl-spiro 4, 5 -dec-6-en-8-one, 1-isopropenyl-4,7,9-trimethyl- and -4,7-dimethyl-spiro[4, 5 -dec-3-en-8-one and 1-isopropenyl-7-Me-4-methylene-spiro 4, 5 -decan-8-one.