Ammonium Chloride → 7-(1-Allylbut-3-enyl)-2-cyclopropyl-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile

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Reaction Conditions

Reaction Steps

Copper (I) iodide (52 mg, 0.27 mmol) was suspended in tetrahydrofuran (3 ml), and under nitrogen atmosphere at −30° C., vinylmagnesium bromide (1 M tetrahydrofuran solution) (2.72 ml, 2.72 mmol) was dropwise added. The solution was stirred at the same temperature for 30 minutes, then a solution of 2-cyclopropyl-7-(l iodomethylbut-3-enyl)-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile (I-298)(425 mg, 0.91 mmol) dissolved in tetrahydrofuran (6 ml) was gradually added. After stirring at the same temperature for 1 hour and 20 minutes and heating up to 0° C., aqueous saturated ammonium chloride solution was added, followed by further stirring for 30 minutes. This was extracted three times with ethyl acetate. The organic layers were combined, washed with saturated brine, and dried over anhydrous sodium sulfate. The insoluble matter was separated by filtration, the solvent was evaporated away, and the resulting residue was purified by middle-pressure liquid chromatography (eluent, n-hexane:ethyl acetate=9:1, v/v) to obtain the entitled compound (243 mg, 73%) as a colorless gel.

Provenance & Evidence