Improved facile synthesis of α-amino phosphonates by the reaction of α-amido sulfones with dialkyl trimethyl silyl phosphites catalyzed by Fe(III) chloride

<p>An improved efficient synthesis of α-amino phosphonates has been discovered by the reaction of <i>N</i>-benzyloxycarbonylamino sulfones with dialkyl trimethyl silyl phosphites in the presence of FeCl₃ as a catalyst. The products were formed in high yields (86–94%) within 2–4 h. The catalyst is inexpensive, easily available, and highly active. The unreacted dialkyl trimetyl silyl phosphites can easily be removed from the products due to their low boiling points. The sulfones can conveniently be prepared and are generally stable.