Abstract
In this paper we describe a useful synthetic procedure leading in very good yields to mono- and bis-α-aminophosphonic acid dialkylesters containing the free phenolic hydroxyl group in a strategic position of the aromatic ring in order to enhance complexation with metal ions. This synthetic procedure is based on the addition of a solution of sodium dialkyl phosphite in phosphite to imine precursors. The addition reaction is highly stereospecific: only one diastereomer for each of the bis-α-aminophosphonic acid dialkylesters is formed. All compounds were characterized by NMR (1H and 31P) and by FAB-MS spectroscopy.