A KINETIC STUDY OF A HALOGENATION OF FEW ANILIDES BY N2,N4,N6-TRICHLORO-2,4,6-TRIAMINO-1,3,5-TRIAZINE

摘要

The kinetics of halogenation of a few anilides using N2,N4N6-trichloro-2,4,6-tri-amino-1,3,5-triazine (trichloromelamine) in pure acetic acid medium in the presence of perchloric acid is reported.The order with respect to trichloromelamine (TCM) is unity.The reactions are exhibiting differential behaviour on acidity.Acetanilide and p-methyl acetanilide show inverse fractional dependence on acidity whereas p-meth-oxy acetanilide is found to have direct unit dependence on acidity.p-Nitro acetanilide behaves differently as it shows zero dependence on acidity.Addition of Cl~- enhances the rate.The replacement of HClO4 by HCl accelerates the reaction.Substituents with electron-releasing groups and electron-withdrawing groups are both accelerating the reaction indicating a breakdown of pa plot.A suitable rate law has been derived.All the facts have been explained on the basis of a plausible mechanism involving the Orton rearrangement.