反应详情

A mixture (20.87 g, 0.1 mole) of 2-bromo-4-chlorobenzothiazole and 2,4-dichlorobenzothiazole and 94% sodium hydroxide (4.68 g, 0.11 mole) in 95% ethanol (200 c.c.) was heated under reflux for 1 hour. After cooling, water (250 c.c.) was added to the reaction solution, followed by ice-cooling. The deposited crystals were filtered and washed with water to obtain 19.86 g of 2-ethoxy-4-chlorobenzothiazole. Yield 92.9%, purity 98.9%, m.p. 43°-45° C.

1. temperatureunder reflux for 1 hour
2. temperatureAfter cooling
3. temperaturecooling
4. filtrationThe deposited crystals were filtered
5. washwashed with water