反应详情

Oxalyl chloride (1.2 mL) and DMF (25 μL) were added to 5-bromonicotinic acid (1.0 g, 4.95 mmol) suspended in CH2Cl2 (30 mL). The resulting mixture was stirred at room temperature for 12 min. It was then concentrated to dryness and azeotroped with toluene. The residual was then dissolved in toluene (30 mL). 3,5-Difluoroaniline (1.0 g, 7.8 mmol) was added followed by triethylamine (1.1 mL, 7.5 mmol). The resulting suspension was stirred at room temperature for 10 min. The reaction mixture was taken in 5% acetic acid(aq) (300 mL) and extracted with ethyl acetate (2×200 mL). The combined organic extract was washed with 1.0 M Na2CO3(aq) (2×100 mL) and brine. The organic layers were combined, dried (Na2SO4) and concentrated to dryness to provide the title compound (1.4 g, 93%). MS (APCI) m/z 313, 315 (M+H)+.

1. concentrationIt was then concentrated to dryness
2. customazeotroped with toluene
3. dissolutionThe residual was then dissolved in toluene (30 mL)
4. stirringThe resulting suspension was stirred at room temperature for 10 min
5. extractionextracted with ethyl acetate (2×200 mL)
6. extractionThe combined organic extract
7. washwas washed with 1.0 M Na2CO3(aq) (2×100 mL) and brine
8. dry with materialdried (Na2SO4)
9. concentrationconcentrated to dryness