Oxidative Chlorination, Desulphonation, or Decarboxylation To Synthesize Pharmaceutical lntermediates: 2,6-Dichlorotoluene, 2,6-Dichloroaniline, and 2,6-Dichlorophenol

摘要

An alternative manufacturing process scheme was developed for 2,6-dichlorotoluene, 2,6-dichlorlaniline, and 2,6-dichlorophenol, involving oxidative chlorination after protection of the starting material in the para position followed by deprotection involving desulphonation or decarboxylation. Oxidative chlorination of 4-methylbenzenesulphonic acid 4-methylbenzoic acid, 4-aminobenzoic acid, and 4-hydroxybenzoic acid by using HCl-H_2O_2, and their subsequent desulphonation or decar-boxtylation, gave a 60-75% yield of the desired product.