Sodium Carbonate → 3-bromo-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyrimidine

Participants

Reaction Conditions

Reaction Steps

3,6-Dibromopyrazolo[1,5-a]pyrimidine (2.0 g, 7.22 mmol) was mixed with 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (1.51 g, 7.22 mmol). Dioxane (36 mL) and 1M Na2CO3 (10.8 mL) were added. The mixture was evacuated and flushed with nitrogen under stirring, then Pd(Ph3P)4 (0.42 g, 0.36 mmol) was added in a counter flow of nitrogen. The reaction mixture was heated to 85° C. under stirring for 16 h, cooled, and poured into a 5-fold excess of water. The product was extracted thrice with CH2Cl2. The organic layer was washed with brine, dried with MgSO4, filtered, and evaporated. The residue was purified by column chromatography (1-5% methanol/DCM) to give 3-bromo-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyrimidine as a yellow solid: LC/MS [M+H]=277.9.

Provenance & Evidence