[1,2]‐Phospha‐Brook Rearrangement as Tool for Generation of Anionic Nucleophiles in Addition Reactions under Brønsted Base Catalysis

Abstract The [1,2]‐phospha‐Brook rearrangement involves the migration of the dialkoxyphosphoryl moiety of the alkoxide of an α‐hydroxyphosphonate from carbon to oxygen to generate an α‐oxygenated carbanion. The alkoxide that is the precursor for the rearrangement is easily accessible by the deprotonation of α‐hydroxyphosphonates or the addition of the anion of secondary phosphites to carbonyl compounds under the influence of a Brønsted base. This review article summarized recent development of the Brønsted base‐catalyzed addition reactions in which the [1,2]‐phospha‐Brook rearrangement is utilized for the generation of carbon‐based anionic nucleophiles.