反应详情

To a solution of 5-bromo-1-methyl-1H-imidazole (10 g, 62 mmol) in dichloromethane (50 mL) was added dropwise ethylmagnesium bromide (3 M in Et2O, 20.7 mL, 62 mmol). After stirring at room temperature for 15 min, the reaction mixture was cooled down to 0° C. with an ice-brine bath and N-methoxy-N-methylbenzamide (9.46 mL, 62 mmol) was added dropwise. The mixture was stirred for 2 h at room temperature. After standing for one night at room temperature, the mixture is worked-up by addition of water (150 mL), then acidified with aq. HCl (1 M) until pH=7. After extraction with dichloromethane (2×100 mL), the organic layers were washed with water (100 mL) then dried over MgSO4 and concentrated in vacuo. The resulting orange solid was washed with pentane to afford (1-methyl-1H-imidazol-5-yl)(phenyl)methanone [8.50 g, yield 66%; HPLC/MS: m/z=187 (M+H); log P(HCOOH)=0.79].

1. temperaturethe reaction mixture was cooled down to 0° C. with an ice-brine bath
2. stirringThe mixture was stirred for 2 h at room temperature
3. waitAfter standing for one night at room temperature
4. extractionAfter extraction with dichloromethane (2×100 mL)
5. washthe organic layers were washed with water (100 mL)
6. dry with materialthen dried over MgSO4
7. concentrationconcentrated in vacuo
8. washThe resulting orange solid was washed with pentane