Lithium Hexamethyldisilazide → 9-Benzenesulfonyl-5-hydroxy-9H-dipyrido[2,3-b;4',3'-d]pyrrole-6-carbonitrile

Participants

Reaction Conditions

Reaction Steps

Lithium bis(trimethylsilyl)amide (9.6 mL, 1N solution in THF, 9.60 mmol) was added dropwise to a cooled (−78° C.) suspension of 1-benzenesulfonyl-2-{[cyanomethyl(toluene-4-sulfonyl)amino]methyl}-1H-pyrrolo[2,3-b]pyridine-3-carboxylic acid methyl ester (1.72 g, 3.19 mmol) in dry THF (50 mL). The reaction mixture was allowed to warm to −30° C., stirred at −30° C. for 2 h, before warming to ambient temperature. The reaction mixture was quenched with saturated aqueous ammonium chloride solution (30 mL) and water (50 mL). The aqueous phase was extracted with DCM (2×20 mL) and the combined organic phase was washed with brine and concentrated in vacuo. The resultant solid was triturated with THF (2×4 mL) to afford the title compound. The filtrate was purified by flash chromatography (silica, 5 g column, Si-SPE, ethyl acetate then 10-20% MeOH in DCM) to afford the remaining title compound. The two batches of material were combined to afford a yellow solid (1.03 g, 90%). LCMS (Method B): RT=3.26 min, M+H+=351.

Provenance & Evidence