Patents
The invention relates to a process for the preparation of optically enriched (-)-(2 S, 4 R)-rose oxide and its isomer (+)-(2 R, 4 S)-rose oxide from racemic citronellol. said process comprising cohalogenating racemic citronellol with a halogenation reagent in anhydrous alcohol to obtain an alkoxy halide, dehydrohalogenating the alkoxy halide to obtain the corresponding 3-octenol derivative, acylating the alcoholic function of the 3 octanol derivative with an acylating agent in presence of a base to give the corresponding acylate, subjecting the acylate so obtained to kinetic resolution using a biocatalyst or an enzyme, separating the mixture of reaction products comprising of optically enriched hydrolysed alcohol and unhydrolysed acylate derivatives, hydrolysing the optically enriched acylate with a base to furnish optically enriched primary alcohol and cyclised the alcohol so obtained with an acid catalyst to produce dextrorotatory (2R, 4S)-rosc oxide, the optically enriched hydrolysed alcohol being directly cyclised with an acid catalyst to produce laevorotatoty (2R,4S)- rose oxide.