Reaction Steps
A mixture of Pd(PPh3)4 (185 mg, 0.16 mmol), 1-chloro-4-(trimethylsilyl)-but-1-en-3-yne (0.776 g, 4.89 mmol), and diethylamine (0.51 mL, 4.93 mmol) in degassed benzene (5 mL) was stirred at 25° C. for 15 minutes. The resultant solution was added to a mixture of Compound 230 (1.50 g, 3.26 mmol) and CuI (124 mg, 0.65 mmol) in degassed benzene (15 mL) via a syringe followed by stirring at 25° C. for one hour. The reaction mixture was quenched by saturated aqueous NH4Cl, extracted with ethyl ether (80 mL), washed with brine, dried over anhydrous Na2SO4, and concentrated in vacuo. Purification of the residue by flash column chromatography (silica gel, 25 percent ethyl ether in petroleum ether) provided a solid product Compound 231 (0.606 g, 32 percent): Rf =0.43 (silica, 50 percent ethyl ether in petroleum ether); IR (CHCl3) νmax 2964, 1721, 1494, 1378, 1305, 1270, 1253, 1202, 1181, 1122, 846 cm-1 ; 1H NMR (300 MHz, CDCl3) δ 8.40 (d, J=8.7 Hz, 1 H, H1), 7.44-7.10 (m, 6 H, H4 and aromatic), 6.99 (dd, J=8.7, 2.4 Hz, 1 H, H2), 5.98 (d, J=1.5 Hz, 1 H, H6), 5.84 (d, J=11.1 Hz, 1 H, olefinic), 5.69 (br d, J=11.1 Hz, 1 H, olefinic), 2.81-2.66 (m, 2 H, H9), 2.41-2.26 (m, 2 H, H7), 2.10-1.86 (m, 2 H, H8), 1.33 (s, 9 H, COC(CH3)3), 0.22 (s, 9 H, SiC(CH3)3); MS (FAB+) m/e (rel intensity) 582 (M+H, 100), 525 (13), 460 (48), 406 (8), 360 (6), 320 (8), 279 (25), 246 (5);HRMS for C34H36NO6Si (M+H), calcd 582.2312, found 582.2322.
