The combination of benzamides/NCS as nitrogen/halogen sources for aminohalogenation of β-nitrostyrenes resulting in dichlorinated haloamides

The combination of benzamide and NCS was found to be an efficient nitrogen/halogen source for aminohalogenation of β-nitrostyrenes. The reaction was convenient to carry out by using 4-dimethylaminopyridine as the catalyst, resulting in vicinal dichlorinated haloamino nitroalkanes with opposite regiochemistry to that generated from other electron-deficient olefins observed previously. The reaction proceeded smoothly at room temperature with good yields and excellent regioselectivities. A mechanism involving a chloronium intermediate was proposed to explain the resulting regiochemistry. The current system explored a new type of nitrogen sources for aminohalogenation of functionalized olefins.