Cesium carbonate → 2-methyl-1-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazol-1-yl]propan-2-ol

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-pyrazole (500 mg, 2.58 mmol) in 2,2-dimethyl-oxirane (3 mL) was added cesium carbonate (130 mg, 0.40 mmol). The reaction was heated at 120° C. for 30 minutes using microwave irradiation. The reaction was cooled then filtered through a plug of cotton wool, flushing with DCM. The filtrate was concentrated in vacuo giving 2-Methyl-1-[4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-pyrazol-1-yl]-propan-2-ol as a beige solid (620 mg, 90%). 1H NMR δ (ppm) (CDCl3): 7.82 (1H, d, J=0.65 Hz), 7.69 (1H, s), 4.07 (2H, s), 1.32 (12H, s), 1.15 (6H, s). 1 Exchangeable proton not observed

Provenance & Evidence