Rapid and Efficient Synthesis of Unsymmetrical Phosphinic Acids R′P(O)OHR″

A new synthesis of unsymmetrical phosphinic acids R′P(O)OHR″ has been evaluated. The first P–C bond was formed by base‐promoted H‐phosphinate alkylation of a protected H‐phosphinate, which is easier and safer to handle. A one‐pot methodology was developed for the second P–C bond formation reaction that involves the sila‐Arbuzov reaction. This methodology was then extended to the synthesis of a dialkylphosphinic acid with an amino functionality. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)