Reaction Steps
A solution of Compound 314 (5.69 g, 14.6 mmol) in dry degassed benzene (120 mL) was added to copper (I) iodide (0.666 g, 3.51 mmol), and to the resulting mixture was added 1-chloro-4-(trimethylsilyl)-but-1-en-3-yne (3.69 g, 23.4 mmol) followed by n-butylamine (2.89 mL, 29.2 mmol) and tetrakis (triphenylphosphine) palladium (0) (1.01 g, 0.877 mmol) in dry degassed benzene (60 mL). The reaction mixture was stirred at 25° C. for 2 hours, diluted with ethyl ether (200 mL), poured into saturated aqueous ammonium chloride (200 mL), and extracted with ethyl ether (2×70 mL). The combined organic layers were dried (MgSO4) and evaporated in vacuo. The residue was purified by flash column chromatography (silica, 25 percent ethyl ether in petroleum ether) to give 5.43 g (73 percent) of Compound 315: white foam; Rf =0.29 (silica, 30 percent ethyl ether in petroleum ether); IR (CHCl3) νmax 2958, 2836, 1717, 1609, 1590, 1493, 1380, 1299, 1251 cm-1 ; 1H NMR (300 MHz, CDCl3) δ 7.94 (d, J=3.0 Hz, 1 H, aromatic), 7.38-7.06 (m, 6 H, aromatic), 6.89 (dd, J=8.9, 3.0 Hz, 1 H, aromatic), 5.92 (d, J=1.6 Hz, 1 H, H6), 5.86 (d, J=11.0 Hz, 1 H, olefinic), 5.65 (br d, J=11.0 Hz, 1 H, olefinic), 3.81 (s, 3 H, OCH3), 2.78-2.62 (m, 2 H, H9), 2.37-2.25 (m, 2 H, H7), 2.05-1.85 (m, 2 H, H8), 0.20 (s, 9 H, Si(CH3)3); 13C NMR (125 MHz, CDCl3) δ 201.2, 157.2, 154.1, 151.0, 129.3, 128.6, 128.5, 125.7, 124.0, 121.4, 120.7, 118.9, 114.8, 114.8, 103.5, 101.5, 90.5, 83.0, 74.6, 57.4, 55.4, 48.4, 38.8, 23.8, 18.2, -0.17; MS (FAB+) m/e (rel intensity) 511 (M+, 100), 390 (8), 362 (9), 176 (11), 120 (10); HRMS for C30H29NO5Si (M+), calcd 511.1815, found 511.1815.
