反应详情

A solution of 6.18 parts of dicyclohexylcarbodiimide in 30 parts by volume of dimethoxyethane is added dropwise, over 1.5 hours, to a stirred solution of 8.49 parts of benzothiazol-2-ylthio succinic acid prepared as in Example 1A in dimethoxyethane (70 parts by volume). The reaction is exothermic and the temperature is maintained at 25°-27° with cooling. When the addition is complete, stirring is continued for a further 1.5 hours and the precipitated dicyclohexylurea is removed by filtration. The filtrate is evaporated in vacuo and the residual solid is recrystallised from a mixture of dichloromethane and cyclohexane to give benzothiazol-2-ylthio succinic anhydride m.p. 129°-129° (with decomposition).

1. temperaturethe temperature is maintained at 25°-27°
2. temperaturewith cooling
3. additionWhen the addition
4. customthe precipitated dicyclohexylurea is removed by filtration
5. customThe filtrate is evaporated in vacuo
6. customthe residual solid is recrystallised from a mixture of dichloromethane and cyclohexane