896722-50-2

98-09-9

896722-50-2

The general procedure for the synthesis of 6-chloro-1-benzenesulfonyl-1H-pyrrolo[2,3-b]pyridine from benzenesulfonyl chloride was as follows: firstly, 6-chloro-7-azaindole (9.3 g, 61.1 mmol) was dissolved in 100 mL of anhydrous tetrahydrofuran (THF) under nitrogen protection. After the reaction mixture was cooled to 0°C, a dispersion of 60% sodium hydride (NaH) in mineral oil (3.5 g, 65.9 mmol) was added. After stirring for 1 h at room temperature, the mixture was again cooled to 0°C and benzenesulfonyl chloride (8.7 mL, 67.2 mmol) dissolved in 20 mL of anhydrous THF was added. The reaction mixture was continued to be stirred at room temperature for 1 hour. Subsequently, ethyl acetate was added to the mixture and the organic layer was washed three times with saturated sodium bicarbonate (NaHCO3) solution, dried over anhydrous sodium sulfate (Na2SO4), filtered and concentrated. The resulting residue was purified by fast chromatography (ether/petroleum ether gradient elution from 1:4 to pure ether) to afford 1-benzenesulfonyl-6-chloro-1H-pyrrolo[2,3-b]pyridine (amorphous solid, 14.4 g, 80.7% yield). Thin layer chromatography (TLC) analysis showed an Rf value of 0.37 (ether/petroleum ether, 1/1). Liquid chromatography-mass spectrometry (LCMS) analysis: retention time (Rt) was 1.98 min and the molecular ion peak ([M + H]+) was 293.