Potassium Carbonate → 5-(6-cyclopropyl-pyridin-2-yl)-2-phenoxymethyl-6,7-dihydro-5H-pyrazolo[1,5-a]pyrazin-4-one

Participants

Reaction Conditions

Reaction Steps

Tetrakis(triphenylphosphine)palladium (0) (7 mg, 0.006 mmol), was added to a stirred suspension of 5-(6-bromo-pyridin-2-yl)-2-phenoxymethyl-6,7-dihydro-5H-pyrazolo[1,5-a]pyrazin-4-one (50 mg, 0.12 mmol), potassium carbonate (52 mg, 0.37 mmol), cyclopropylboronic acid (21.5 mg, 0.25 mmol) in a mixture of DMF (0.5 mL) and 1,4-dioxane (0.5 mL) in a sealed tube and under nitrogen. The mixture was stirred at 150° C. for 15 minutes under microwave irradiation. The mixture was diluted with water and extracted with AcOEt. The organic layer was washed with brine, dried (MgSO4), filtered and the solvents evaporated in vacuo. The crude product was purified by flash column chromatography (silica; AcOEt in DCM 0/100 to 20/80). The desired fractions were collected and the solvents evaporated in vacuo. The product was triturated with heptane to yield 5-(6-cyclopropyl-pyridin-2-yl)-2-phenoxymethyl-6,7-dihydro-5H-pyrazolo[1,5-a]pyrazin-4-one (28 mg, 62% yield) as a white solid. 1H NMR (500 MHz, CDCl3) δ ppm 0.93-1.03 (m, 4H), 1.97-2.06 (m, 1H), 4.44-4.58 (m, 4H), 5.12 (s, 2H), 6.93-7.04 (m, 4H), 7.05 (s, 1H), 7.27-7.34 (m, 2H), 7.58 (t, J=7.8 Hz, 1H), 7.74-7.80 (m, 1H).

Provenance & Evidence