Reaction Steps
A mixture of Pd(PPh3)4 (1.12 g, 0.97 mmol), 1-chloro-4-(trimethylsilyl)-but-1-3n-3-yne (4.60 g, 28.98 mmol), and n-propylamine (2.38 mL, 28.98 mmol) in degassed benzene (100 mL) was stirred at 25° C. for 15 minutes. The resultant solution was added to a mixture of Compound 143b (79:21, mixture of diastereomers, 11.80 g, 19.32 mmol) and CuI (0.74 g, 3.86 mmol) in degassed benzene (300 mL) via a syringe followed by stirring at 25° C. for five hours. The reaction was quenched with saturated aqueous NH4Cl, extracted with ethyl ether (500 mL), washed with brine, dried over anhydrous Na2SO4, and concentrated in vacuo. Purification of the crude product by flash column chromatography (silica gel, 20 percent ethyl ether in petroleum ether) gave Compound 232 (12.3 g, 87 percent): amorphous solid; Rf =0.51 (silica, 25 percent ethyl ether in petroleum ether); IR (CHCl3) νmax 2957, 2932, 1716, 1613, 1506, 1495, 1384, 1344, 1306, 1253, 1200, 1093, 1025, 858, 844 cm-1 ; 1H NMR (300 MHz, CDCl3) δ 8.19 (d, J=8.1 Hz, 1 H, aromatic), 7.97 (d, J=7.7 Hz, 1 H, aromatic), 7.80-7.17 (m, 9 H, H1, H4and aromatic), 6.93-6.84 (m, 1 H, H2), 5.96 (br s, 0.79 H, H6), 5.93 (br s, 0.21 H, H6), 5.88-5.77 (m, 2 H, olefinic), 5.58 (s, 2 H, benzylic), 5.03 (br s, 0.79 H, H10), 4.73 (br s, 0.21 H, H10), 2.67-2.50 (m, 1 H, H7), 2.39-2.26 (m, 1 H, H7), 2.16-1.91 (m, 3 H, H8 and H9), 1.84-1.70 (m, 1 H, H8 or H9), 1.02 (s, 1.89 H, SiC(CH3)3), 0.90 (s, 7.11 H, SiC(CH3)3), 0.27 (s, 9 H, Si(CH3)3), 0.18 (s, 3 H, SiCH3), 0.16 (s, 3 H, SiCH3); MS (FAB+) m/e (rel intensity) 865 (M+Cs, 72), 732 (42), 675 (82), 639 (28), 585 (100), 450 (34), 330 (39), 279 (52), 198 (42); HRMS for C42H48N2O6Si2Cs (M+Cs), calcd 865.2105, found 865.2111.
