Triethylamine → 1-Methyl-3-(1-methyl-4-piperindin-4-yl)-5-hydroxy-1H-indole2,6-difluorobenzenesulfonicacidesteroxalate

Participants

Reaction Steps

A solution of 2,6-difluorobenzenesulfonyl chloride (312 mg, 1.47 mmol) in methylene chloride (2 mL) was added to a solution of 1-methyl-3-(1-methylpiperidin-4-yl)-5-hydroxy-1H-indole (327 mg, 1.34 mmol) and triethylamine (226 μL, 1.6 mmol) in tetrahydrofuran (10 mL), methylene chloride (2 mL) and DMF (6 mL). The reaction mixture was stirred at ambient temperature for 1 h. The reaction mixture was diluted with water and ethyl acetate, basified with saturated NaHCO3, and extracted with ethyl acetate. The ethyl acetate extracts were washed with water, brine, dried (NaSO4), filtered and concentrated under reduced pressure to give 550 mg of a white solid. The product was purified by flash chromatography (silica gel, 5%,10% 2M ammonia in methanol/methylene chloride) to give 440 mg (78%) of homogeneous title compound as a white foam. The product was crystallized as the oxalic acid salt from ethyl acetate to give a white powder: mp=195-198° C. dec; MS(m/e): 421 (M+1); Calculated for C23H22F2N2O3S.C2H2O4: C, 54.11; H, 4.74; N, 5.49. Found: C, 53.86; H, 4.62; N, 5.29.

Provenance & Evidence