1H-Pyrrolo(2,3-b)pyridine → Tert-butyl 4-(1H-pyrrolo[2,3-B]pyridin-3-YL)-5,6-dihydropyridine-1(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

Potassium hydroxide (1.90 g, 33.86 mmol) was added to 1H-pyrrolo[2,3-b]pyridine (1.0 g, 8.46 mmol) and tert-butyl 4-oxopiperidine-1-carboxylate (3.37 g, 16.93 mmol) in methanol (25 mL) at ambient temperature, then the resulting solution was stirred at 65° C. for 18 hours. The mixture was cooled to ambient temperature, quenched in dilute aqueous ammonium chloride (80 mL) and extracted with ethyl acetate. The extract was washed sequentially with water and saturated brine, dried over MgSO4, concentrated by evaporation and purified by flash silica chromatography, using 5% MeOH in DCM eluent. Pure fractions were combined and concentrated by evaporation, then triturated with ether to give a colourless precipitate. The precipitate was collected by filtration, washed with ether and air dried to afford tert-butyl 4-(1H-pyrrolo[2,3-b]pyridin-3-yl)-5,6-dihydropyridine-1(2H)-carboxylate (1.37 g, 54%) as a colourless solid.

Provenance & Evidence