Photo-enhanced Reduction of Conjugated Enones with NaBH4

摘要

The reduction of some cyclic conjugated enones with electron-donating substituent on C-3 by sodium borohydride was accelerated on irradiation. The photo-enhanced reduction seems to undergo through zwitterionic species formed from the (n, π*) triplet state of conjugated enones, followed by hydride attack to yield unsaturated or saturated alcohols.