Preparation of Alkyl N-Alkylphosphonamidates by the Microwave-Assisted Selective Monoaminolysis of Dialkyl Phosphites.

The title compounds, (RO)(NHR')P(O)H, were synthesized earlier from P-chloro intermediates by substitutions or from dialkyl phosphites by reaction with organometallic reagents. Instead of these not clear-cut and not efficient transformations, a green, solvent- and catalyst-free synthesis of alkyl phosphonamidates has been developed by the microwave-assisted aminolysis of dialkyl phosphites. The monosubstitution was fully selective. Under more forcing conditions, an interesting side reaction was observed. The resulting products may be valuable reagents to prepare α-hydroxy- and α-aminophosphonic derivatives.