反应详情

In argon atmosphere, to a solution of 5.59 g (17.61 mmol) of N-[(1E)-1-(6-bromopyridin-2-yl)ethylidene]-2,4,6-trimethylaniline in 140 ml of dry toluene cooled to 0° C., a solution of 2.53 g (35.2 mmol) AlMe3 in 20 ml of dry toluene was added dropwise for 10 min. This mixture was slowly warmed to room temperature, stirred for 25 min at 40° C., cooled to 0° C., and then 140 ml of 5% KOH was added dropwise for 1 h. The aqueous layer was separated, the organic layer was washed with 100 ml of water, then 100 ml of brine, dried over Na2SO4, and then evaporated to dryness. The crude product was purified by flash chromatography on silica gel 60 (40-63 um, eluent: dichloromethane-ethyl acetate=20:1, vol.). Yield 2.80 g (47%) of yellow crystalline solid. Anal. calc. for C17H21BrN2: C, 61.27; H, 6.35; N, 8.41. Found: C, 61.14; H, 6.26; N, 8.31. 1H NMR (CDCl3): δ 7.63 (dd, J=8.0 Hz, J=0.6 Hz, 1H, 5-H in pyridine), 7.49 (t, J=7.6 Hz, 1H, 4-H in pyridine), 7.32 (dd, J=8.0 Hz, J=0.6 Hz, 1H, 3-H in pyridine), 6.78 (s, 2H, 3, 5-H in mesityl), 3.65 (br.s, 1H, NH), 2.21 (s, 3H, 4-Me in mesityl), 2.01 (s, 6H, 2, 6-Me in mesityl), 1.46 (s, 6H, CMe2).

1. temperaturecooled to 0° C.
2. customThe aqueous layer was separated
3. washthe organic layer was washed with 100 ml of water
4. dry with material100 ml of brine, dried over Na2SO4
5. customevaporated to dryness
6. customThe crude product was purified by flash chromatography on silica gel 60 (40-63 um, eluent: dichloromethane-ethyl acetate=20:1, vol.)