反应详情

3-Benzyloxy-4-methoxybenzaldehyde (8.0 g, 33.05 mmol), ammonium acetate (2.55 g, 33.05 mmol) and nitroethane (120 ml) were stirred under reflux for 22 h. The reaction mixture was cooled to rt and nitroethane was removed in vacuo. The solid residue was dissolved in ethyl acetate (200 ml), washed with water (40 ml) and brine (2×40 ml), dried (MgSO4) and concentrated in vacuo. Recrystallisation from ethanol afforded the title compound (6.19 g, 63%) as yellow crystals. mp=102-104° C. 1H NMR (270 MHz; CDCl3) 2.27 (3H, s, CH3), 3.94 (3H, s, OCH3), 5.19 (2H, s, CH2Ph), 6.91 (1H, d, J=2.0 Hz, CH), 6.94 (1H, d, J=8.4 Hz, CH), 7.05 (1H, dd, J=8.4, 2.0 Hz, CH), 7.30-7.43 (4H, m, 4×CH), 7.97 (1H, s, CH). 13C NMR (67.5 MHz; CDCl3) 14.03 (CH3), 56.15 (OCH3), 71.25 (CH2Ph), 111.69 (CH), 115.77 (CH), 124.93 (C), 124.94 (CH), 127.16 (CH), 128.19 (CH), 128.83 (CH), 133.84 (CH), 136.65 (C), 145.92 (C), 148.00 (C), 151.51 (C). LC/MS (APCI−) tr=1.07 min, m/z 297.93 (M−H)−.

1. temperatureunder reflux for 22 h
2. customnitroethane was removed in vacuo
3. dissolutionThe solid residue was dissolved in ethyl acetate (200 ml)
4. washwashed with water (40 ml) and brine (2×40 ml)
5. dry with materialdried (MgSO4)
6. concentrationconcentrated in vacuo
7. customRecrystallisation from ethanol