Water → HCID 178477916, compound

Participants

Reaction Steps

N-Bromosuccinimide (4.70 g, 26 mmol) was added in portions over 5 minutes to a stirred solution of 3-(2,4-Bis-benzyloxy-5-chloro-phenyl)-1H-pyrazole (10.29 g 26 mmol) in dichloromethane (200 ml). The reaction mixture was stirred at ambient temperature for 2 hours then water (200 ml) was added and vigorous stirring continued for 10 minutes. The phases were separated and the organic phase was washed with water (3×100 ml), saturated aqueous sodium chloride solution (2×100mi) and dried over sodium sulphate. The mixture was filtered and filtrate solvents were removed in vacuo to afford an off-white solid, which was triturated with ethyl acetate/hexane (1:20) mixture to give 3-(2,4-Bis-benzyloxy-5-chloro-phenyl)-4-bromo-1H-pyrazole (11.80 g, 97%) as off-white solid.

Provenance & Evidence