5-Alkylbicyclo[4.3.0]non-1-en-3-one and 5-alkylbicyclo[4.3.0]nonane-3-one perfume compositions

Abstract

Novel bicyclic ketones having the structure: ##STR1## wherein R is a C.sub.1 -C.sub.5 alkyl group, either straight-chain or branched, and saturated analogs have been prepared. These compounds exhibit floral and woody odors and/or desirable flavor properties, and are useful as fragrance and/or flavor materials. The compounds are conveniently prepared from alkylidene cyclopentanones by Michael addition with alkyl metalloacetoacetates and subsequent decarboxylative cyclization of the adducts. The saturated analogs may then be prepared by hydrogenation.

Dependencies are inferred from the claim text.