Synthesis of phosphorous acid and its derivatives based on the reaction of elemental phosphorus (P4) and aqueous solution of choline in the presence of the hydroxides of earth alkali metals

A nonchloric method for the synthesis of phosphorous acid and barium and calcium phosphites is proposed, involving the reaction of elemental phosphorus (P₄) with aqueous barium and calcium hydroxides in the presence of quaternary ammonium base (choline). Conditions for the preparation of high‐purity phosphorous acid based on the oxidation of the hypophosphite ion to the phosphite ion in a strong alkali medium were studied. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:517–519, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20472