反应详情

A suspension of 22 g of the N-(n-butylaminocarbonyl)-2,3-dihydro-2,2-dimethyl-7-benzofuransulfonamide prepared in Example 3, in 125 ml of xylene containing 0.3 g of DABCO was heated at 130°-135° C. while 5.3 ml of phosgene was added portionwise at a rate to maintain a reflux temperature of 130°-135° C. The mixture was refluxed for an additional 1.5 hours, cooled under nitrogen, and concentrated to dryness in vacuo. A sample of the crude oily product displayed a characteristic sulfonyl isocyanate band in the IR at 2200 cm-1.

1. additionwas added portionwise at a rate
2. temperatureto maintain a reflux temperature of 130°-135° C
3. temperatureThe mixture was refluxed for an additional 1.5 hours
4. temperaturecooled under nitrogen
5. concentrationconcentrated to dryness in vacuo