KHSO4-mediated synthesis of α-amino phosphonates under a neat condition and their 31P NMR chemical shift assignments

A simple and efficient method for the synthesis of α-amino phosphonates has been accomplished from aromatic aldehydes, diethyl phosphite, and aromatic (or) aliphatic amines using potassium hydrogen sulfate as a catalyst under solvent free condition at ambient temperature and these compounds are characterized by 31P NMR with reference to H3PO4.