Hydrochloric Acid → 2-Benzothiazolecarboxylicacid,6-fluoro-,methylester(9CI)

Hydrogen chloride gas was introduced over 3 minutes into a flask containing a solution of 137.2 mg of 2-cyano-6-fluorobenzothiazole in 2.7 ml of methanol with stirring, the reaction mixture being cooled in an ice-water bath. The reaction mixture was stirred at the same temperature for 2 minutes, and then water was added thereto. The resulting mixture was extracted with ethyl acetate to give an extract which was washed first with water and then an aqueous sodium chloride solution and then dried over sodium sulfate. The solvent was then removed by evaporation under reduced pressure and the resulting residue was purified by column chromatography through silica gel using a 5:1 by volume mixture of hexane and ethyl acetate as the eluent, to give 106.8 mg (yield 68%) of the title compound as a pale yellow crystalline solid.

1. temperaturethe reaction mixture being cooled in an ice-water bath
2. stirringThe reaction mixture was stirred at the same temperature for 2 minutes
3. extractionThe resulting mixture was extracted with ethyl acetate
4. customto give
5. extractionan extract which
6. washwas washed first with water
7. dry with materialan aqueous sodium chloride solution and then dried over sodium sulfate
8. customThe solvent was then removed by evaporation under reduced pressure
9. customthe resulting residue was purified by column chromatography through silica gel using a 5:1
10. additionby volume mixture of hexane and ethyl acetate as the eluent

ORD record

ord-c604962ac5544b72add0bee016115b2c

Source dataset

uspto-grants-1998_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05736487