1262035-61-9

General procedure for the synthesis of 5-bromo-1-cyclopropyl-1H-imidazole from 1-cyclopropyl-1H-imidazole: In a 350 mL four-neck flask, 1-cyclopropyl-1H-imidazole (2.58 g, 23.9 mmol, 1.00 equiv.) was mixed with dichloromethane (100 mL) to form a colorless solution. 1,3-Dibromo-5,5-dimethylimidazolidine-2,4-dione (3.48 g, 12.2 mmol, 0.51 eq.) dissolved in dichloromethane (100 mL) was added slowly and dropwise at 5°C and the reaction mixture was stirred for 2.5 hr. at 0°C to 5°C. Post-treatment: the reaction mixture was burst with 100 mL of sodium sulfite solution. The reaction mixture was extracted with dichloromethane (2 x 200 mL). The organic layer was washed with water/sodium chloride solution, dried with sodium sulfate and concentrated. The crude product was purified by rapid chromatography (silica gel, 120 g, 25% to 100% ethyl acetate in heptane solution) to give 1.21 g of the title compound as a colorless oil.MS (ESI): 187.9/189.1 [M + H]+.

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