The present invention relates to the field of perfumery and concerns the use as perfuming ingredient of ketones of formula wherein n represents 0, 1 or 2, m represents 0, 1 or 2, the dotted lines represent only single bonds or one double bond and two single bonds, R.sup.1 represents a hydrogen atom or a methyl or ethyl group, said R.sup.1 group being located at any of the position of the cyclic moiety, R.sup.2 represents a C.sub.1-C.sub.3 O-alkyl or O-alkenyl group or a substituted or unsubstituted ethylene or cyclopropyl group. Said compounds are useful to impart a clean and natural fruity, pineapple odor type. The present invention concerns also the compositions or articles containing said compounds (I) as well as some of said compounds (I). ##STR00001##

The present invention relates to the field of perfumery and concerns the use as perfuming ingredient of ketones of formula wherein n represents 0, 1 or 2, m represents 0, 1 or 2, the dotted lines represent only single bonds or one double bond and two single bonds, R.sup.1 represents a hydrogen atom or a methyl or ethyl group, said R.sup.1 group being located at any of the position of the cyclic moiety, R.sup.2 represents a C.sub.1-C.sub.3 O-alkyl or O-alkenyl group or a substituted or unsubstituted ethylene or cyclopropyl group. Said compounds are useful to impart a clean and natural fruity, pineapple odor type. The present invention concerns also the compositions or articles containing said compounds (I) as well as some of said compounds (I). ##STR00001##

A method of producing alpha-tocotrienol quinone or a stereoisomer thereof, the method comprising selective opening of alpha-tocotrienol chroman to alpha-tocotrienol quinone in the presence of non-alpha tocotrienol chromans by oxidizing alpha-to-cotrienol with a metal salt oxidizing agent, wherein the stoichiometric ratio of metal salt oxidizing agent/alpha-tocotrienol is at least 4:1 and wherein said metal oxidizing agent is added in sequential additions, in order to reduce oxidation of any amounts of non-alpha tocotrienol chromans that might have been present in the starting alpha-tocotrienol chroman material. This process uses conditions favoring oxidation rates of the alpha tocotrienol chroman vs. the non-alpha tocotrienol chromans.

A method of producing alpha-tocotrienol quinone or a stereoisomer thereof, the method comprising selective opening of alpha-tocotrienol chroman to alpha-tocotrienol quinone in the presence of non-alpha tocotrienol chromans by oxidizing alpha-to-cotrienol with a metal salt oxidizing agent, wherein the stoichiometric ratio of metal salt oxidizing agent/alpha-tocotrienol is at least 4:1 and wherein said metal oxidizing agent is added in sequential additions, in order to reduce oxidation of any amounts of non-alpha tocotrienol chromans that might have been present in the starting alpha-tocotrienol chroman material. This process uses conditions favoring oxidation rates of the alpha tocotrienol chroman vs. the non-alpha tocotrienol chromans.