反应详情

(3,5-Dimethoxyphenyl)-(3-ethoxy-4-methoxyphenyl)methanone (0.63 g, 2.00 mmol), cyanomethylphosphonic acid diethyl ester (0.63 ml, 3.98 mmol) in anhydrous THF (10 ml), and lithium bis(trimethylsilyl)amide (1.0 M solution in THF, 3.98 ml, 3.98 mmol) were treated in the same manner as described above for the synthesis of 3-(3,5-dimethoxy-phenyl)-3-(3-methoxy-phenyl)-acrylonitrile. The crude was purified via flash column chromatography (5% EtOAc in hexane gradient to 40% EtOAc in hexane in about 40 min.) to give 3-(3,5-dimethoxy-phenyl)-3-(3-ethoxy-4-methoxy-phenyl)-acrylonitrile as an off-white solid (0.60 g, 89%): mp, 110-112° C.; 1HNMR (CDCl3) δ 7.04-6.82 (m, 3H, Ar), 6.55-6.43 (m, 3H, Ar), 5.65 (s, 0.50H, double bond proton of one isomer), 5.43 (s, 0.5H, double bond proton of the other isomer), 4.13-3.99 (m, 2H, CH2CH3 from the two isomers), 3.92 & 3.90 (s, 3H, single OCH3 group from the two isomers), 3.80 & 3.77 (s, 6H, 2OCH3 from the two isomers), 1.49-1.41 (two triplets, 3H, CH2CH3 from the two isomers); 13C NMR (CDCl3) δ 162.9, 162.8, 160.9, 160.8, 151.7, 151.1, 148.3, 148.0, 141.6, 139.1, 131.2, 129.3, 123.3, 122.2, 118.2, 114.2, 112.7, 111.2, 111.1, 107.8, 107.2, 102.3, 102.2, 93.8, 93.2, 64.7, 56.2, 56.1, 55.7, 14.8; Anal. Calcd. For C20H21NO4: C, 70.78; H, 6.24; N, 4.13. Found: C, 70.62; H, 6.25; N, 4.01.

1. customThe crude was purified via flash column chromatography (5% EtOAc in hexane gradient to 40% EtOAc in hexane in about 40 min.)