Acetic Acid → tert-butyl 3-(6H-imidazo[1,5-a]pyrrolo[2,3-e]pyrazin-1-yl)-4-methylpiperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 4-methyl-3-(6-tosyl-6H-imidazo[1,5-a]pyrrolo[2,3-e]pyrazin-1-yl)piperidine-1-carboxylate (19.0 g, 37.3 mmol) in 1,4-dioxane (100 mL) was added aqueous NaOH (1N, 74.6 mL, 74.6 mmol). The reaction was heated at about 60° C. for about 30 min and allowed to cool to ambient temperature followed by the addition of 10% aqueous AcOH (250 mL). The mixture was extracted with EtOAc (2×250 mL) and the combined organic layers were washed with brine (200 mL), dried over anhydrous Na2SO4, and filtered. The filtrate was concentrated under reduced pressure and purified by silica gel chromatography (330 g) eluting with a gradient of 10-70% EtOAc in heptane to provide tert-butyl 3-(6H-imidazo[1,5-a]pyrrolo[2,3-e]pyrazin-1-yl)-4-methylpiperidine-1-carboxylate (12.3 g, 93%) as a white foam: LC/MS (Table 2, Method a) Rt=1.96 min; MS m/z: 356 (M+H)+.

Provenance & Evidence