To aluminum trichloride (8.89 g, 66.7 mmol) was added methylene chloride (150 mL) under an atmosphere of nitrogen below 5° C. Into this, 5-bromo-7-azaindole (67, 1.64 g, 8.34 mmol) in methylene chloride (20 mL) was added. The reaction was stirred for 60.0 minutes and 2,6-difluoro-3-(propane-1-sulfonylamino)-benzoyl chloride (46, 3.50 g, 11.8 mmol) in methylene chloride (20 mL) was added. The reaction was stirred for 6 hours and warmed to room temperature overnight. The reaction mixture was poured into water and extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, filtrated and concentrated. The desired compound was isolated by silica gel column chromatography (methylene chloride/methanol 5%) to give a white solid (P-0773, 1.2 g, 31.4%). MS (ESI) [M+H+]+=460.0, 462.0.
