4-Methoxybenzoic Acid → HCID 58465615, compound

Participants

Reaction Steps

To a solution of 4-methoxybenzoic acid (0.187 g, 1.23 mmol) dissolved in N,N-dimethylformamide (5 mL) and triethylamine (0.428 mL, 3.07 mmol) was added tetramethylfluoroformamidinium hexafluorophosphate (0.406 g, 1.54 mmol) and the reaction mixture was stirred for 15 minutes. Ethyl 4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine-2-carboxylate (0.2 g, 1.02 mmol) was added and the reaction continued to stir at room temperature for 5 hours. The reaction mixture was diluted with water and extracted with EtOAc (3×). The combined organic layers were washed with water, brine, dried over anhydrous Na2SO4, filtered and concentrated. The residue was purified via silica gel chromatography (0-90% EtOAc/hexane) to afford ethyl 5-(4-methoxybenzoyl)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine-2-carboxylate Intermediate 27 (0.359 g, 100%). LC-MS: (FA) ES+330.

Provenance & Evidence