反应详情

Under nitrogen, a solution of 5.87 g (27.7 mmol) 1-tert-butyl-1H-pyrazole-4-carboxylic acid methoxy-methyl-amide in 55 ml THF is cooled to 0° C. and 18.5 ml (55.5 mmol) of a 3 M solution of methylmagnesium bromide in diethyl ether is added dropwise at 0° C. The reaction mixture is stirred for 18 hours at room temperature. The reaction mixture is partitioned between brine and ethyl acetate. The organic phase is dried over sodium sulfate and evaporated. The residue is chromatographed on a silica gel column with cyclohexane/ethyl acetate as eluent to afford 1-(1-tert-butyl-1H-pyrazol-4-yl)-ethanone as white solid; HPLC/MS 1.87 min (B), [M+H] 167;

1. customThe reaction mixture is partitioned between brine and ethyl acetate
2. dry with materialThe organic phase is dried over sodium sulfate
3. customevaporated
4. customThe residue is chromatographed on a silica gel column with cyclohexane/ethyl acetate as eluent