Reduction of α,β-unsaturated carbonyl compounds with sodium borohydride in the diethyl ether/methanol/pentafluorophenol solvent system. Use of N,N,N',N'-tetramethylethylenediamine and 1-hexene as borane scavengers

Article abstract of DOI:10.1016/0022-1139(93)05005-L

Pentafluorophenol acts as an efficient proton source for sodium borohydride reductions in diethyl ether containing methanol.This system allows for the regioselective reduction of α,β-unsaturated carbonyl compounds to the corresponding allylic alcohols in high yield.Use of either 1-hexene or N,N,N',N'-tetramethylethylenediamine as borane scavengers moderately improved the regioselectivity of this reaction.Fortunately, sodium trispentafluorophenoxyborohydride, generated in situ, gave regiospecific 1,2-reduction of α,β-unsaturated carbonyl compounds.