26723-60-4

26638-53-9

26723-60-4

The general procedure for the synthesis of 3-chloro-6,11-dihydro-6-methyl-dibenzo[c,f][1,2]thiazepin-11(6H)-one 5,5-dioxide from 3-chloro-6-methyl-dibenzo[c,f][1,2]thiazepin-11-ol 5,5-dioxide was as follows: to a solution of 3-chloro-6-methyl-dibenzo[c,f][1,2]thiazepin- 11(6H)-one 5,5-dioxide (62.5 g) to a solution of methanol (500 ml), sodium borohydride (15.04 g) was slowly added at 0-5 °C. The reaction mixture was stirred at 0-5 °C for 30 min, followed by continued stirring at room temperature for 30-60 min. After completion of the reaction, the solid product was collected by filtration and washed with methanol. The resulting solid was dried under constant weight to afford 3-chloro-6,11-dihydro-6-methyldibenzo[c,f][1,2]thiazepin-11-ol 5,5-dioxide in 90-95% yield.