Benzenesulfonyl chloride → methyl 1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of tetrabutylammonium bromide (154 mg, 0.48 mmol) and 1H-pyrrolo[2,3-b]pyridin-5-carboxylic acid methyl ester (2.8 g, 15.9 mmol) in dichloromethane (40 mL) was added sodium hydroxide powder (1.9 g, 47.7 mmol) at 0° C. The mixture was stirred at 0° C. for 5 min. Benzene sulfonyl chloride (3 mL, 23.8 mmol) was added slowly to the above mixture at 0° C. and the resulting mixture was stirred at 0° C. for another 15 min before it was warmed to 25° C. and kept at that temperature for 12 h. The reaction mixture was filtered and then concentrated in vacuo to afford 1-benzenesulfonyl-1H-pyrrolo[2,3-b]pyridin-5-carboxylic acid methyl ester as a light yellow solid which was washed with hexane to give a white solid (4.6 g, 90%): 1H NMR (400 MHz, CDCl3) δ ppm 3.95 (s, 3H), 6.69 (d, J=4.0 Hz, 1H), 7.51 (m, 2H), 7.61 (m, 1H), 7.82 (d, J=4.0 Hz, 1H), 8.22 (m, 2H), 8.51 (d, J=2.0 Hz, 1H), 9.08 (d, J=2.0 Hz, 1H).

Provenance & Evidence