反应详情

To a solution of 2-trifluoromethyl-5-bromopyridine (5.0 g, 22 mmol) in Et2O (50 mL) was added sec-BuLi (0.91 M in cyclohexane, 24 mL, 22 mmol) at −78° C. After 10 minutes of stirring, N,N-dimethylaminoacetamide (2.3 mL, 24 mmol) dissolved in Et2O (10 mL) was added drop wise. Stirring was continued at −78° C. for 1 h and then at rt over night. The reaction mixture was poured into water (100 mL) and the water phase was extracted with Et2O (3×100 mL). Combined organics were washed with water and brine and dried (MgSO4). After careful evaporation of the solvent, the crude was purified by column chromotography (SiO2, pentane/ether 9/1) to give the title compound (2.3 g, 12 mmol, 54%) as a light yellow solid.

1. additionwas added drop wise
2. stirringStirring
3. waitwas continued at −78° C. for 1 h
4. waitat rt over night
5. extractionthe water phase was extracted with Et2O (3×100 mL)
6. washCombined organics were washed with water and brine
7. dry with materialdried (MgSO4)
8. customAfter careful evaporation of the solvent
9. customthe crude was purified by column chromotography (SiO2, pentane/ether 9/1)