Carbonyl reduction

Reduction at a carbonyl group, for example conversion of a ketone to an alcohol. In an enone, 1,2- and 1,4-reduction produce different functional-group patterns.

Conversion of an aldehyde or ketone carbonyl into a methylene through hydrazone formation and base-promoted nitrogen extrusion. The strongly basic, often heated conditions must be compatible with the other functional groups.

A cerium(III)-assisted borohydride reduction often used to favour 1,2-reduction of an enone to an allylic alcohol. Actual selectivity remains substrate- and condition-dependent.