反应详情

82.5 ml of pyridine and 18.9 ml of methyl chloroformate were added to a solution of 55.0 g of 4-(benzothiazol-2-ylmethoxy)-2-methylaniline [prepared as described in step (b) above] in 400 ml of dimethylformamide cooled in an ice-water bath and the resulting mixture was stirred at the same temperature for 2 hours. At the end of this time, the reaction mixture was poured into water resulting in the precipitation of a crystalline solid which was washed with water and then further washed with diethyl ether to give a crude crystalline solid. This was recrystallised from a 4:1 by volume mixture of tetrachloromethane and acetone to give 36.2 g (yield 54%) of the title compound as a solid having a melting point of 147° to 149° C.

1. temperaturecooled in an ice-water bath
2. washwas washed with water
3. washfurther washed with diethyl ether
4. customto give a crude crystalline solid
5. customThis was recrystallised from a 4:1 by volume mixture of tetrachloromethane and acetone