p-Bromobenzenesulfonyl chloride → N-(Benzo[b]thiophen-2-yl)-4-bromobenzenesulfonamide

Participants

Reaction Steps

To a stirred solution of compound 1-C (9.28 g, 49.9 mmol) in pyridine (100 mL) and methylene chloride (50 mL), cooled on an ice bath, was added 4-bromobenzene-1-sulfonyl chloride (12.8 g, 49.9 mmol), portion-wise over a period of 4 minutes. The reaction mixture was allowed to warm to ambient temperature and stirred for 18 h. The reaction mixture was concentrated under reduced pressure, the crude residue partitioned between EtOAc (500 mL) and 1N HCl (250 mL), the layers separated, the organic phase washed with 1N HCl (125 mL), brine, dried over MgSO4, filtered and evaporated in vacuo. The crude residue was purified by flash column chromatography (SiO2) eluting with an EtOAc-Heptane gradient to afford 13.5 g of compound 361-A as a tan powder. 1H-NMR (DMSO-d6) δ: 6.89 (s, 1H), 7.33-7.20 (m, 2H), 7.75-7.64 (m, 3H), 7.84-7.76 (m, 3H), 11.30 (s, 1H); MS: m/z 366.1 (M-H)−.

Provenance & Evidence