Hydrochloric Acid → HCID 131720185, compound

800 mg of 6-(3-trifluoromethylphenyl)-1H-imidazo-[1,2-b]pyrazole and 5 ml of dimethylformamide were slowly added dropwise at room temperature, whilst stirring, to 76 mg of a 55% w/w suspension of sodium hydride in mineral oil, which was itself suspended in 10 ml of dimethylformamide, and the resulting mixture was stirred for 30 minutes at room temperature. 497 mg of ethyl bromide were then added dropwise, whilst cooling with ice water, and the resulting mixture was stirred at room temperature for 30 minutes. The reaction mixture was then partitioned between ethyl acetate and water. The ethyl acetate layer was washed With water and with an aqueous solution of sodium chloride, in that order, and dried over anhydrous magnesium sulfate. The solvent was then removed by evaporation under reduced pressure. The product was then purified by silica gel column chromatography using a 1:1 by volume mixture of ethyl acetate and hexane as the eluent, to afford the title compound as an oil. The hydrochloride was formed from this oil by adding a 4N solution of hydrogen chloride in dioxane, and this was recrystallized from a mixture of acetone and diethyl ether, to afford 750 mg of 1-ethyl-6-(3-trifluoromethyl-phenyl)-1M-imidazo[1,2-b]pyrazole hydrochloride as pale brown prismatic crystals, melting at 135° to 141° C.

1. customthis was recrystallized from a mixture of acetone and diethyl ether

ORD record

ord-ac441bafd0e546e7922d71a089661a28

Source dataset

uspto-grants-1997_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05665752