The Study on Chlorination by Sulfuryl Chloride of Benzene/Pyridine Carboxamides and Carbonitriles

In the chlorination of N-[2-aryl-1-(1-piperidinylcarbonyl)ethenyl]arenecarboxamides, it has been found that a derivative having two methoxy substituents on the arenecarbonyl ring undergoes chlorination on the same ring rather than converting into the expected enamine bond chlorination product. Based on the above results, the chlorination of benzamides/nicotinamides by sulfuryl chloride (SO2Cl2) has been studied. We developed a method of synthesizing aromatic chlorinated compounds by treating aromatic amides or nitriles with SO2Cl2 in dichloromethane at 0oC without catalyst. This is a new mild method and gives good yields, especially when benzene ring is substituted by amide or cyano group together with the alkoxy group.