反应详情

To a solution of 1-methyl-5-trimethylsilanylethynyl-1H-imidazole (1.78 g, 10 mmol) in THF (30 mL) was slowly added a solution of nBuLi in hexanes (2.5M, 4.4 mL) at −78° C. and the resulting suspension was stirred at the same temperature for 1 h. Trimethylsilyl isocyanate (from Aldrich, 85% pure. 11.76 mmol, 1.6 mL) was slowly added to this suspension at −78° C. After stirring at −78° C. for another 30 minutes the reaction mixture was allowed to warm up slowly by removing the cooling bath. Water (2 mL) and MeOH (1 mL) was added to quench the reaction and the mixture was stirred overnight. More water and EtOAc was added to facilitate the extraction. The combined organic layers were dried over Na2SO4, filtered, and then concentrated on a rotavap and the residue was purified on a silica gel column (eluent: 40-60% EtOAc in hexanes) to give the desired product as a white solid in 26% yield (387 mg).

1. stirringAfter stirring at −78° C. for another 30 minutes the reaction mixture
2. temperatureto warm up slowly
3. customby removing the cooling bath
4. additionWater (2 mL) and MeOH (1 mL) was added
5. customto quench
6. customthe reaction
7. stirringthe mixture was stirred overnight
8. extractionthe extraction
9. dry with materialThe combined organic layers were dried over Na2SO4
10. filtrationfiltered
11. concentrationconcentrated on a rotavap
12. customthe residue was purified on a silica gel column (eluent: 40-60% EtOAc in hexanes)