Benzyl Bromide → 1-Benzyl-4-iodo-1H-pyrazole

Participants

Reaction Steps

A 250-mL round-bottomed flask was charged with 4-iodo-1H-pyrazole (17 g, 87.63 mmol, 1.00 equiv) in N,N-dimethylformamide (150 mL) To this was added sodium hydride (3.6 g, 105.00 mmol, 1.20 equiv, 70%) in several batches at 0° C., followed by addition of 1-(bromomethyl)benzene (16.5 g, 96.49 mmol, 1.10 equiv) dropwise at 0° C. The resulting solution was allowed to warm up to room temperature and stirred for 2 hours at room temperature. The reaction was then quenched by the addition of water/ice (200 mL). The resulting solution was extracted with ethyl acetate (3×200 mL). Combined organic layers were dried over anhydrous sodium sulfate, filtered off and concentrated on a rotary evaporator affording 1-benzyl-4-iodo-1H-pyrazole as yellow solid (22 g, 80%).

Provenance & Evidence