Benzenesulfonyl chloride → 6-Chloro-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine

Participants

Reaction Steps

6-Chloro-7-azaindole (9.3 g, 61.1 mmol), prepared as described (Synthesis, 1992), was dissolved in 100 ml anhydrous THF under N2. At 0° C., a 60% dispersion of NaH 3.5 g (65.9 mmol) in mineral oil was added. After stirring for 1 hour at room temperature, the mixture was cooled (0° C.) and 8.7 ml (67.2 mmol) benzenesulfonyl chloride dissolved in 20 ml anhydrous THF was added. The reaction mixture was stirred at room temperature for 1 hour. Ethyl acetate was added to the mixture and the organic layer was washed three times with a saturated NaHCO3 solution, dried (Na2SO4), filtered and concentrated. The resulting residue was purified by flash chromatography (diethyl ether/PE gradient (1:4 to pure diethyl ether) to give 1-benzenesulfonyl-6-chloro-1H-pyrrolo[2,3-b]pyridine (amorphous, 14.4 g, 80.7%) (TLC diethyl ether/PE (1/1) Rf 0.37). LCMS; Rt: 1.98 min, ([M+H]+=293).

Provenance & Evidence