Methyl iodide → 5-Bromo-2-ethyl-1,3-benzothiazole

Participants

Reaction Steps

A 0° C. solution of diisopropylamine (340 μL, 2.41 mmol) in THF (3 mL) was treated with 2.5M n-butyllithium in hexanes (0.88 mL), stirred for 20 minutes, added to a −78° C. solution of 5-bromo-2-methyl-1,3-benzothiazole (250 mg, 1.10 mmol) in THF (3 mL), stirred for 30 minutes, treated with iodomethane (340 μL, 5.50 mmol), and stirred for 1 hour. The mixture was diluted with ethyl acetate (50 mL), washed sequentially with 1M HCl (5 mL), water (5 mL), and brine (5 mL), dried (MgSO4), filtered, and concentrated. The concentrate was purified by flash column chromatography on silica gel with 30% hexanes/dichloromethane to provide the desired product. MS (DCI) m/e 242 (M+H)+.

Provenance & Evidence