反应详情

To 20 ml of a solution of 1.15 g of 4-bromo-1-(4,4-dimethyl-1,3-oxazolin-2-yl)benzene in tetrahydrofuran, 3.23 ml of n-BuLi (1.53M hexane solution) were added dropwise at −78° C. under stirring, followed by stirring at the same temperature for 15 minutes. To the reaction mixture was added dropwise a solution of 0.8 g of 1-tert-butyl-5-isopropylpyrazole-3-carbaldehyde in 5 ml of tetrahydrofuran. The resulting mixture was stirred for 30 minutes. After the reaction, 10 ml of a saturated aqueous solution of ammonium chloride were added to the reaction mixture and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with saturated saline, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue so obtained was subjected to chromatography on a silica gel column (developing solvent: 50% ethyl acetate/n-hexane), whereby 0.82 g of the title compound was obtained in the form of a colorless oil.

1. stirringby stirring at the same temperature for 15 minutes
2. stirringThe resulting mixture was stirred for 30 minutes
3. additionwere added to the reaction mixture
4. extractionthe resulting mixture was extracted with ethyl acetate
5. washThe organic layer was washed with saturated saline
6. dry with materialdried over anhydrous magnesium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe residue so obtained