反应详情

To a stirred solution of (3,5-dimethyl-1H-pyrazol-4-yl)acetic acid tert.-butyl ester (10 g) in dimethylformamid (50 ml) at room temperature is added 1-bromomethyl-4-iodobenzene (15.5 g) and potassium carbonate (8.0 g). After 15 h of stirring, water is added and the reaction mixture is extracted twice with ethyl acetate. The organic layer is washed several times with water, dried over magnesium sulfate and concentrated in vacuo. The residue is purified by flash chromatography (4:1 to 3:2 cyclohexane:ethyl acetate) to yield 1-(4-iodobenzyl)-3,5-dimethyl-1H-pyrazol-4-yl-acetic acid tert.-butyl ester (12.2 g). [M+H]=427; HPLC retention time 1.57 min (Method E).

1. extractionthe reaction mixture is extracted twice with ethyl acetate
2. washThe organic layer is washed several times with water
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated in vacuo
5. customThe residue is purified by flash chromatography (4:1 to 3:2 cyclohexane:ethyl acetate)