反应详情

A mixture of 6-methylpyridine-2-carboxaldehyde (2.12 g, 17.50 mmol), aniline (1.63 g, 17.50 mmol), diphenyl phosphite (4.92 g, 21.00 mmol), and zirconyl chloride octahydrate (0.56 g, 1.75 mmol) was stirred at room temperature 1 h. The reaction mixture was extracted with CH2Cl2 (3×50 mL), and the CH2Cl2 solution was washed with water (2×20 mL), dried over anhydrous Na2SO4, filtered, and evaporated to dryness under reduced pressure. The residue was purified by MPLC on silica gel using a mixture of EtOAc and hexane as eluent to give the titled compound (6.96 g, 92%) as a white solid. 1H NMR (400 MHz, CDCl3): δ 7.51 (t, 1H, J=7.8 Hz), 7.38 (dd, 1H, J=7.6, 2.0 Hz), 7.27-7.22 (m, 4H), 7.19-7.15 (m, 2H), 7.14-7.07 (m, 4H), 7.05-7.02 (m, 3H), 6.80-6.74 (m, 3H), 5.53 (pseudo t, 1H, J=7.4 Hz), 5.36 (dd, 1H, J=21.0, 8.2 Hz), 2.54 (s, 3H).

1. extractionThe reaction mixture was extracted with CH2Cl2 (3×50 mL)
2. washthe CH2Cl2 solution was washed with water (2×20 mL)
3. dry with materialdried over anhydrous Na2SO4
4. filtrationfiltered
5. customevaporated to dryness under reduced pressure
6. customThe residue was purified by MPLC on silica gel using
7. additiona mixture of EtOAc and hexane as eluent