Recent Synthetic Applications of the Birch Reduction

The Birch reduction has found a renaissance during the last two decades. In this Synpacts article a short summary of selected recent synthetic applications will be provided. 1,4-Cyclohexadienes, which are formed by Birch reduction in one step, are suitable precursors for radical reactions and are used as surrogates for difficult to handle substances. Their rearomatization under acidic conditions offers easy access to selectively alkylated arenes. Additionally, the Birch reduction of benzoic acids and subsequent trapping affords spiro compounds in high yields. Very recently, it was shown that 1,3-cyclohexadienes are directly available by Birch reduction in a one-pot reaction as well.