Deamination of 1-Aminoalkylphosphonic Acids: Reaction Intermediates and Selectivity.

Deamination of 1-aminoalkylphosphonic acids in the reaction with HNO 2 (generated "in situ" from NaNO 2 ) yields a mixture of substitution products (1-hydroxyalkylphosphonic acids), elimination products (vinylphosphonic acid derivatives), rearrangement and substitution products (2-hydroxylkylphosphonic acids) as well as H 3 PO 4 . The variety of formed reaction products suggests that 1-phosphonoalkylium ions may be intermediates in such deamination reactions.