STUDIES ON ORGANOPHOSPHORUS COMPOUNDS .54. SYNTHESIS OF 1-HYDROXY-1-ALKYL-2-AMINOETHYLPHOSPHONIC ACID AND 1-HYDROXY-1-ARYL-2-AMINOETHYLPHOSPHONIC ACID AND DERIVATIVES THEREOF

An improved method is developed for the synthesis of l-hydroxy-l-alkyl(aryl)-2-aminoethylphosphonic acids based on hydrogenation of dialkyl l-hydroxy-l-alkyl(aryl)-2-nitroethylphosphonates over Raney nickel in acidic medium followed by hydrolysis. The instability of dialkyl l-hydroxy-l-alkyl(aryl)-2-aminoethylphosphonates was rationalized by the formation of a reactive three-membered ring oxide species as the result of inter molecular interaction. The presence of p-toluenesulfonic acid during hydrogenation affords the corresponding ammonium tosylate which can be used directly for the formation of new phosphonopeptides containing a free hydroxyl group. © 1991, Taylor & Francis Group, LLC. All rights reserved.