反应详情

温度

-78 °C

To a solution of 1.08 g (14 mmol) dimethylsulfoxide in 100 ml dichloromethane cooled to −78° C. was added a solution of 1.82 g (14 mmol) oxalyl chloride in 7 ml dichloromethane. The mixture was stirred for 50 minutes at −78° C. and then a solution of 0.620 g (3 mmol) 2-(2,6-diethyl-benzyl)-4,5-dihydro-1H-imidazole in 80 ml dichloromethane was added and stirring continued at −78° C. for 90 minutes. Then 2.90 g triethylamine were added and the reaction mixture warmed to ambient temperature and stirring continued for 2 hours. Concentrated ammonia was added and the reaction mixture extracted with ethyl acetate, the combined extracts washed with brine, dried over Na2SO4, filtered and evaporated. Purification on silica gel by flash-chromatography with a heptane/ethyl acetate gradient followed by trituration of residue of the collected and evaporated fractions in tert.-butyl methyl ether provided 0.475 g 2-(2,6-diethyl-benzyl)-1H-imidazole as colourless solid: MS (ISP): 215.2 ((M+H)+.).

1. stirringstirring
2. waitcontinued at −78° C. for 90 minutes
3. temperaturethe reaction mixture warmed to ambient temperature
4. stirringstirring
5. waitcontinued for 2 hours
6. extractionthe reaction mixture extracted with ethyl acetate
7. washthe combined extracts washed with brine
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. customevaporated
11. customPurification on silica gel by flash-chromatography with a heptane/ethyl acetate gradient
12. customcollected
13. customevaporated fractions in tert.-butyl methyl ether