Reductive transformations mediated by zinc dust in acetic acid

Zinc dust in glacial acetic acid (Zn/HOAc) reagent system is an important traditional reductive reagent in organic chemistry, which still plays a unique role in a wide range of functional group transformations in organic synthesis. We now present a systematic outline of the applications of this reduction system in practical organic synthesis. This article mainly surveys the hydrogenative reductions of CC, CC, CO, CN, CS, N–N, NN, NO, N–O, O–O, S–S, reductive cleavages of C−halo, C–N, C–O, C–S, and some interesting reductive rearrangement reactions mediated by zinc in acetic acid, respectively. The relevant plausible reaction mechanisms under Zn/HOAc conditions were also discussed briefly.