Process for the hydrogenation of citral to citronellal and of citronellal to citronellol using chromium-promoted Raney nickel catalyst

摘要

A process is provided for the semihydrogenation of the olefinic group in the conjugated position to the carbonyl group in citral and homologues thereof to form citronellal and homologues thereof, and also for the hydrogenation of the aldehyde group of citronellal to form citronellol and homologues thereof. The dienic aldehyde is hydrogenated with hydrogen in the presence of chromium-promoted Raney nickel catalyst, and optionally, an inert solvent such as a lower aliphatic alcohol. The process is of particular application to the hydrogenation of citral and citronellal to citronellol.