Hydrochloric Acid → 2-Chloro-1,3-benzothiazol-6-amine

Temperature

120 °C

Compound 2 (1.96 g, 9.14 mmol) was dissolved in ethanol (150 mL) and purified water (100 mL), and the solution was added with anhydrous tin(II) chloride (20.7 g, 91.7 mmol). The mixture was added with 4.8 mol/L hydrochloric acid (20 mL, 96 mmol) and refluxed at 120° C. After disappearance of the starting materials was confirmed by thin layer chromatography (developing solvent: dichloromethane), the mixture was basified with aqueous sodium hydroxide. The precipitates were removed by filtration, After, ethanol was evaporated, the residue was extracted three times with ethyl acetate. Then organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (developing solvent: ethyl acetate/n-hexane=1/1) to obtain Compound 3 as white solid (1.02 g, 61% yield).

1. custompurified water (100 mL)
2. customThe precipitates were removed by filtration
3. customAfter, ethanol was evaporated
4. extractionthe residue was extracted three times with ethyl acetate
5. washThen organic layer was washed with saturated brine
6. dry with materialdried over anhydrous sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe residue was purified by silica gel column chromatography (developing solvent: ethyl acetate/n-hexane=1/1)

ORD record

ord-622ea407545b4c0ebb8418f493ce2f27

Source dataset

uspto-grants-2009_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07524876B2