反应详情

Following the procedure in Example 3, the reaction was carried out with 3b (1.0 g, 3.23 mmol), LiCl, predried under vacuum at 120° C. for a period of 24 h (0.82 g, 19.4 mmol), CuCl (1.60 g, 16.2 mmol), Pd(PPh3)4 (0.19 g, 0.16 mmol) and ethyl (E)-3-(tributylstannyl)-2-pentenoate (1.62 g, 3.88 mmol) in dry DMSO (35 mL). The crude product was subjected to flash chromatography (hexanes/ethyl acetate 95:5) to afford 4b as a yellow oil (0.82 g, 82%). IR (CH2Cl2, NaCl,cm−1) 2982, 1713, 1640, 1593, 1560, 1453, 1392, 1266, 1186, 1040, 743; 1H NMR (300 MHz, CDCl3) δ0.99 (t, J=7.6 Hz, 3H), 1.30 (t, J=7.1 Hz, 3H), 2.99 (q, J=7.6 Hz, 2H), 3.43 (s, 3H), 4.01 (s, 3H), 4.21 (q, J=7 Hz, 2H), 4.49 (s, 2H), 4.73 (s, 2H), 5.81 (s, 1H), 6.69 (d, J=5 Hz, 1H), 8.11 (d, J=5 Hz, 1H); 13C NMR (75 MHz, CDCl3) δ12.46, 14.43, 26.58, 54.05, 55.58, 60.26, 62.05, 96.96, 116.27, 116.85, 120.00, 146.36, 153.34, 159.37, 163.42, 165.90; HRMS (EI) m/z calcd for C16H23NO5 (M+) 309.1576, found 309.1587; LRMS (EI) m/z 309(M+, 32), 277(42), 236(100), 190(84), 174(73), 160(22), 77(10).