Potassium Hydroxide → Allyl 2-amino-5-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-carboxylate

Participants

Reaction Steps

3-(1,3-Dioxolan-2-yl)-1,1,1-trifluoro-propan-2-one (55.58 g, 301.9 mmol) and allyl 3,5-diamino-1H-pyrazole-4-carboxylate (55 g, 301.9 mmol) were dissolved in 1,4-dioxane (330 mL). KOH (1.694 g, 30.19 mmol) was added and the yellow suspension was stirred at room temperature for 4 h30 min. The reaction mixture was heated at 90° C. for 16 h. The mixture was cooled down to room temperature. The reaction mixture was concentrated onto silica and purified by column chromatography (CombiFlash Companion XL, 1.5 kg column, 0.5 to 40% EtOAc in DCM) to afford allyl 2-amino-5-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-carboxylate 4d as a bright yellow solid (68 g, 79% yield).

Provenance & Evidence