反应详情

A 500 ml reactor equipped with mechanical stirrer, thermometer and condenser is loaded with 5 g of 2-acetylamino-4,5,6,7-tetrahydro-benzothiazole-6-carboxylic acid [(I), R=—NH—CO—CH3] suspended in 80 ml of N,N-dimethylformamide; then 2.32 g of triethylamine are added. A solution consisting of 6.3 g of diphenylphosphoryl azide (DPPA) dissolved in 7 ml N,N-dimethylformamide is dropped therein in 2 hours. The reaction mixture gradually solubilizes during the addition until complete dissolution. After 6 hours the reaction solution is dropped in 1 liter of a methanol solution containing 8 ml of 37% hydrochloric acid at 60° C. The mixture is left to cool, then extracted twice with 100 ml of methylene chloride, discarding the organic phase. The aqueous phase is concentrated to a residue that is crystallized from i-propanol-water to obtain 3.6 g of a white solid.

1. customA 500 ml reactor equipped with mechanical stirrer
2. additionis dropped
3. additionThe reaction mixture gradually solubilizes during the addition until complete dissolution
4. waitThe mixture is left
5. temperatureto cool
6. extractionextracted twice with 100 ml of methylene chloride
7. concentrationThe aqueous phase is concentrated to a residue that
8. customis crystallized from i-propanol-water