Alkylation of Phenyl Phosphinic Acid

Phosphinic acids have been used as intermediates in the preparation of unsymmetrical tertiary phosphine oxides,1 including optically active oxides. These phosphinic acid derivatives are prepared by the Arbuzov rearrangement of a phosphonite,2 which, in turn, usually comes from the corresponding phosphine dichloride. This route to phosphinic acid works well but involves exceptionally malodorus, air sensitive, hydrolytically unstable intermediates. We wish to report a simple method to prepare phenylphosphinic acids which utilizes odorless, stable solid species.