反应详情

N-Bromosuccinimide (387 mg, 2.17 mmol), α,α'-azobis(isobutyronitrile) (catalytic), 2'-(N-t-butylsulfamoyl)-4-methylbiphenyl (from Step C) (550 mg, 1.81 mmol) and carbon tetrachloride (50 ml) were heated with stirring at reflux for 3 hours. After cooling to room temperature the mixture was filtered and the filtrate evaporated to dryness. Flash chromatography (silica gel, initially 10 and then 20% ethyl acetate-hexane) afforded the title compound [699 mg, 77% pure (the remainder of the material was the corresponding dibromo derivative)] as a white solid; 1H NMR (300 MHz, CDCl3) δ8.17 (dd, J=7.5, 1.6 Hz, 1H), 7.68-7.45 (m, 6H), 7.31 (dd, J=7.5, 1.6 Hz, 1H), 4.55 (s, 2H), 3.52 (s, 1H), 1.00 (s, 9H).

1. temperatureat reflux for 3 hours
2. filtrationwas filtered
3. customthe filtrate evaporated to dryness