An easy access to unsymmetrical ureas: a photocatalytic approach to the Lossen rearrangement
作者:Arvind K. Yadav、Vishnu P. Srivastava、Lal Dhar S. Yadav
DOI:10.1039/c4ra03805c
日期:——
synthesis of unsymmetrical ureas from various hydroxamic acids and amines has been developed. Plausibly, the protocol involves visible-light-initiated in situ formation of Vilsmeier–Haack reagent and COBr2 with CBr4 and a catalytic amount of DMF in the presence of Ru(bpy)3Cl2 as a photocatalyst to bring about the Lossenrearrangement at room temperature.