Trifluoroacetic acid → (R)-N-(Piperidin-3-yl)-6-(pyrazolo[1,5-a]pyridin-3-yl)pyrazin-2-amine

Participants

Reaction Steps

Trifluoroacetic acid (0.35 mL, 4.56 mmol) was added to a solution of (R)-tert-butyl 3-(6-(pyrazolo[1,5-a]pyridin-3-yl)pyrazin-2-ylamino)piperidine-1-carboxylate (Preparation 28a, 0.30 g, 0.76 mmol) in methylene chloride (10 mL) and the resulting solution was stirred at ambient temperature overnight and then at 50° C. for additional 24 h. The solvent was then evaporated and the residue was redissolved in methylene chloride and washed with a 10% aqueous sodium hydroxide solution. The organic phase was dried over magnesium sulphate, filtered and the solvent was evaporated. The crude product was purified by flash chromatography (10-15% MeOH/CH2Cl2/NH3) to yield the title compound (0.125 g, 56%) as an oil.

Provenance & Evidence