6.4 g of (+/-)-cis-1,2-dimethoxy-4-(2-aminocyclohexyl)benzene are dissolved in 150 ml of methylene chloride and 9 ml of triethylamine. A solution of 11.2 g of 4-p-toluenesulfonamidobenzoyl chloride in 200 ml of methylene chloride is added dropwise at RT in the course of 3 h, and the mixture is extracted after stirring for 1 h with 100 ml each of water, 2N hydrochloric acid, satd. sodium hydrogencarbonate solution and water again. The organic phase is dried using sodium sulfate, concentrated and crystallized from ethyl acetate. 3.9 g (28.2% of theory) of the title compound of m.p. 174-176° C. are obtained.
