'New' Reagents for the 'Old' Pinacol Coupling Reaction

摘要

An old-timer in the history of chemistry, the pinacol coupling, was first described over 130 years ago in a publication on the synthesis of pinacois. Today this reaction is still a versatile tool for chemists. This "longevity" can be explained by thecontinuous development of improved reagents and by the intrisic elegance of the method for the preparation of 1,2-diols (pinacols) by the reductive coupling of carbonyl compounds. Starting with two carbonyl functionalities, a C- C bond is formed and twonew adjacent slereocenters created. 1,2-Diols are versatile intermediates in synthesis; for example, they can be used for the preparation of ketones by the pinacol rearrangement or alkenes by the McMurry reaction (Scheme 1).