SYNTHESIS OF PHOSPHORUS-CONTAINING CARBOXYLIC ACIDS BASED ON BIS(TRIMETHYLSlLYL)HYPOPHOSPHITE

Abstract

Silylation of ammonium hypophosphite (1) with hexamethyldisilasane (HMDS) followed by alkylation of the intermediate his(trimethylsilyl)hypophosphite (2) with methylchloroacetate in the presence of HMDS gives O-trimethylsilylhis(methoxycarbonylmethyl)phosphinate (3) and O.O-bis(trimethylsilyl)-methoxycarbonylmethylphosphonite (4). Methanolysis of phosphinate 3 gives his(methoxycarbonyl-methyl)phosphinic acid (5). the hydrolysis of which leads to his(hydroxycarbonylmethyl)phosphinic acid (6). Treatment of the acids 5 and 6 with sodium hydroxide gives trisodium salt (7).

Key Words:

• bis(hydroxycarbonylmethyl)phosphinic acid
• bis(trimethylsilyl)bypophosphite
• alkylation
• O-trimethylsilylbis(methoxycarbonylmethyl)phosphinate.
• O.O-bis(trimethylsilyl)methoxycarbonylmethyl-phosphonite
• methanolysis
• hydrolysis.