Diisopropylamine → 1-(1-benzenesulfonyl-5-methoxy-1H-pyrrolo[2,3-b]pyridin-2-yl)-2-(tetrahydro-furan-2-yl)-ethanol

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-benzenesulfonyl-5-methoxy-1H-pyrrolo[2,3-b]pyridine (prepared as in Example 10, 6 g, 20.8 mmol) in dry tetrahydrofuran (40 mL) at −78° C. was added freshly prepared lithium diisopropylamide [prepared by adding 1.6 M n-butyllithium in n-hexane (19.5 mL, 31.2 mmol) to a 0° C. solution of diisopropylamine (4.7 mL, 32.8 mmol) in dry tetrahydrofuran (20 mL)] dropwise. The mixture was stirred at −78° C. for 5 min and then treated with (tetrahydro-furan-2-yl)-acetaldehyde (3.5 g, 30.7 mmol) dropwise. The resulting mixture was stirred at −78° C. for 1 h and quenched with brine. The mixture was extracted with ethyl acetate (2×200 mL), washed with brine, dried over anhydrous sodium sulfate and concentrated in vacuo. Purification by flash silica gel chromatography (silica gel from QingDao, 200-300 mesh, glass column from Shanghai SD company, 25% ethyl acetate/hexanes) afforded 1-(1-benzenesulfonyl-5-methoxy-1H-pyrrolo[2,3-b]pyridin-2-yl)-2-(tetrahydro-furan-2-yl)-ethanol (2.5 g, 30%) as a white solid: LC/MS m/e calcd for C21H22N2O5S [M+H]+ 403.47, observed 403.2.

Provenance & Evidence