Dichloromethane → Ethyl 4-(pyrazolo[1,5-a]pyrimidin-3-yl)benzoate

Participants

Reaction Conditions

Reaction Steps

Water (160 mL) was added dropwise at room temperature to a mixture of 4-ethoxycarbonylphenylboronic acid (50 g, 0.26 mol), 3-bromopyrazolo[1,5-a]pyrimidine (56.25 g, 0.28 mol), Pd(ddpf)Cl2.CH2Cl2 (4.25 g, 5.21 mmol), and Cs2CO3 (169.42 g, 0.52 mol) in 1,4-dioxane (1 L). The reaction mixture was then heated 85° C. for 4 h. The reaction mixture was cooled, poured into water and extracted with EtOAc (2×300 mL). The combined organic layers were dried over Na2SO4, filtered, and the filtrate was concentrated under reduced pressure. The crude product was purified by silica gel chromatography eluting with a gradient of petroleum ether: EtOAc (100:10 to 3:1) to deliver the title compound (64 g, 93%) as a yellow solid.

Provenance & Evidence