Reaction Steps
The procedure for 40 was used with 69 (1.22 g, 1.04 μmol), NiCl2.6H2O (0.12 g, 0.52 mmol) and NaBH4 (0.079 g, 2.08 mmol) to yield 70 (0.80 g, 65%) after flash column chromatography (EtOAc/hexane 1:9) as a colorless oil: IR (CHCl3) 2956, 2929, 2855, 1713, 1615, 1518, 1461, 1388, 1251, 1077, 1037, 836, 773 cm−1; 1H NMR (300 MHz, CDCl3) δ 7.70-7.66 (m, 6H), 7.57-7.40 (m, 1H), 7.07-7.04 (m, 2H), 5.92-5.77 (m, 2H), 5.65 (m, 1H), 5.64 (s, 1H), 5.52 (m, 1H), 4.78 (m, 1H), 4.30 (dd, J=11.2, 4.6 Hz, 1H), 4.14 (m, 2H), 3.94 (s, 3H), 3.79 (d, J=3.9 Hz, 2H), 3.73 (t, J=11.1 Hz, 1H), 3.61 (m, 1H), 2.92-2.79 (m, 2H), 2.72 (t, J=7.4 Hz, 2H), 2.65 (m, 1H), 2.22 (m, 1H), 1.91-1.71 (m, 4H), 1.65-1.56 (m, 3H), 1.51 (m, 1H), 1.43 (d, J=7.1 Hz, 3H), 1.35 (m, 1H), 1.20 (d, J=6.7 Hz, 3H), 1.14-1.12 (m, 21H), 1.08 (d, J=6.2 Hz, 3H), 1.05-1.03 (m, 9H), 0.96 (d, J=6.7 Hz, 3H), 0.34-0.25 (m, 18H); 13C NMR (75 MHz, CDCl3) 6 211.5, 159.8, 144.4, 144.3, 134.3, 132.9, 132.2, 130.9, 128.6, 127.6, 127.1, 126.8, 113.4, 100.8, 86.7, 83.0, 80.1, 72.8, 72.2, 66.4, 65.0, 55.0, 48.2, 42.3, 41.6, 40.6, 38.0, 35.7, 33.5, 31.2, 27.6, 26.2, 25.91, 25.87, 23.9, 19.4, 18.4, 18.05, 17.99, 14.8, 13.2, 12.0, 9.5, −3.0, −3.6, −3.8, −4.2, −4.3, −4.4; LRMS (ESI) 1197.7 [M+Na]+, 684.2, 541.1; HRMS (ESI) calcd for C71H110O8Si3Na 1197.7406 [M+Na]+, found 1197.7411; [α]20D+4.6 (c 1.1, CHCl3).
