o-Toluenesulfonyl chloride → 4-Bromo-1-(2-methyl-benzenesulfonyl)-1H-indole

Participants

Reaction Steps

Aq. 2.5 M NaOH (5 mL) was added to a stirring mixture of 4-bromo-1H-indole (1000 mg, 5.3 mmol), 2-methylbenzenesulfonyl chloride (1100 mg, 5.6 mmol) and tetrabutylammonium hydrogen sulfate (173 mg, 0.5 mmol) in DCM (10 mL). The reaction mixture was stirred at ambient temperature overnight. The mixture was diluted with DCM and water and the layers were separated. DCM was washed with water 2 times, dried (MgSO2) and concentrated to give 1.6 g of crude material that was purified using flash chromatography (SiO2, eluent EtOAc:hexane 9:1) giving the title product (1 g, 54%). MS (ESI+) for C15H12BrNO2S m/z 350 (M+H)+.

Provenance & Evidence