反应详情

A mixture (11.30 g, 0.05 mole) of 2-bromo-4-chlorobenzothiazole and 2,4-dichlorobenzothiazole and 94% sodium hydroxide (2.34 g, 0.055 mole) in isopropanol (100 c.c.) was heated under reflux for 1 hour. Water was added and the alcohol was distilled azeotropically together with water. The resulting oily substance was extracted with chloroform, and the chloroform layer was washed with water. The solvent was then removed under reducing pressure to obtain 10.92 g of 2-isopropoxy-4-chlorobenzothiazole as a yellow viscous liquid. Yield 95.9%, purity 97.7%, b.p. 95°-96° C./0.2 mmHg.

1. temperatureunder reflux for 1 hour
2. distillationthe alcohol was distilled azeotropically together with water
3. extractionThe resulting oily substance was extracted with chloroform
4. washthe chloroform layer was washed with water
5. customThe solvent was then removed