To a solution of ethyl 5-chloro-7-(tetrahydro-2H-pyran-4-ylamino)pyrazolo[1,5-a]pyrimidine-2-carboxylate (5.88 g, 18.1 mmol) in N,N-dimethylacetamide (50 mL) was added triethylamine (5.50 g, 54.3 mmol) and pyrrolidine (1.59 mL, 19.0 mmol) at 0° C. The mixture was heated at 60° C. for 20 h. And then pyrrolidine (1.59 mL, 19.0 mmol) was added and heated at 60° C. for 24 h. After being cooled to ambient temperature, the reaction mixture was poured into water. The resulting precipitate was collected to give ethyl 5-pyrrolidin-1-yl-7-(tetrahydro-2H-pyran-4-ylamino)pyrazolo[1,5-a]pyrimidine-2-carboxylate. MS (APCI): m/z 360 (M+H).
