Mechanistic and Synthetic Aspects of the Benzilic Acid and Ester Rearrangements

Since its discovery the Benzilic acid rearrangement has been the subject of a number of mechanistic studies and successfully employed in key steps in the synthesis of a number of important target molecules. In this review we look at the advances that have been made over the last 20 years in understanding the mechanism of this rearrangement (including the stereochemical aspects), whilst reviewing some important syntheses where this particular rearrangement was used as a key step. Keywords: Benzilic acid rearrangement, benzilic ester rearrangement, retro-benzilic acid rearrangement, [1,2] rearrangement, synthesis