反应详情

A mixture of 2-amino-6-methylbenzothiazole (15 g, 91.3 mmol), ethylene glycol (22.26 g, 0.36 mol) and 50% w/v KOH (180 ml) was heated under reflux for 62 h. On cooling to room temperature, toluene (60 ml) was added and the reaction mixture was cooled in an ice-bath and acidified with acetic acid (final pH 5-6). The reaction mixture was extracted with toluene (5×300 ml) and the combined organic extracts were washed with brine (2×200 ml), dried (MgSO4) and the solvent removed under reduced pressure to give the title compound (11.1 g, 86%) as a yellow solid which was used without further purification.

1. temperaturewas heated
2. temperatureunder reflux for 62 h
3. temperaturethe reaction mixture was cooled in an ice-bath
4. extractionThe reaction mixture was extracted with toluene (5×300 ml)
5. washthe combined organic extracts were washed with brine (2×200 ml)
6. dry with materialdried (MgSO4)
7. customthe solvent removed under reduced pressure