Amine-free approach toward N-toluenesulfonyl amidine construction: a phosphite-mediated Beckmann-like coupling of oximes and p-toluenesulfonyl azide

Angew Chem Int Ed Engl. 2013 Oct 25;52(44):11589-93. doi: 10.1002/anie.201305141. Epub 2013 Sep 5.

Abstract

Atom hopping: A chlorophosphite-mediated Beckmann ligation of oximes and p-toluenesulfonyl azide gives access to N-sulfonyl phosphoramidines in good to excellent yields. The reaction proceeds under exceptionally mild conditions and constitutes a bioorthogonal approach toward amidines by avoiding the use of amines and transition-metal catalysts. dmp-ol=3,3-dimethylpropanediol.

Keywords: Beckmann rearrangement; amidines; azides; oximes; rearrangement.