K3PO4-catalyzed regiospecific aminobromination of beta-nitrostyrene derivatives with N-bromoacetamide as aminobrominating agent.

A very simple, efficient, and regiospecific protocol for aminobromination of a wide scope of beta-nitrostyrene derivatives with N-bromoacetamide (NBA) as nitrogen/bromine sources has been developed by using K(3)PO(4) as catalyst. The reaction proceeded smoothly and cleanly to give the bromoamines in good to excellent yields (78-99%) within 24 h in CH(2)Cl(2) at room temperature without protection of inert gases. A possible mechanism involving a nucleophilic conjugate addition was proposed.