Synthetic variations based on low-valent chromium:: new developments

This article presents an overview of the synthetic chemistry of low-valent chromium, presumably Cr(II) species, and highlights most of the recent developments. These organometallic reactions represent a convenient strategy for the construction of carbon-carbon bonds displaying unique elements of stereocontrol, chemoselectivity, and functional-group compatibility. The introduction of milder protocols, catalytic versions, and the discovery of ligand tuning effects as a means of controlling carbanion selectivity, are the most salient improvements in this expansive field.