Synthesis of unsymmetrical urea from aryl- or pyridyl carboxamides and aminopyridines using PhI(OAc)₂via in situ formation of aryl- or pyridyl isocyanates

Abstract

A tandem synthesis of unsymmetrical urea (N-aryl-N'-pyridylurea and N,N'-bipyridylurea) from aryl- or pyridyl carboxamides and aminopyridines via Hofmann rearrangement has been developed. In particular, benzamides, picolinamide, nicotinamide, and isonicotinamide generate...