Reaction Steps
1,5-Cyclooctadiene-bis(methyldiphenylphosphine)iridium hexafluorophosphate (33 mg) was dissolved in THF (10 mL) and the resulting red solution was degassed in an argon stream. Hydrogen was then bubbled through the solution, until the colour had changed to yellow. The solution was then degassed again in an argon stream. A solution of 521 (4.59 g, 4.16 mmol) in THF (30 mL) was degassed and added. The mixture was stirred at rt overnight, then concentrated. The residue was taken up in a mixture of acetone (10:1, 44 mL). Mercuric bromide (1.78 g, 8.32 mmol) and mercuric oxide (1.69 g, 6.24 mmol) were added to the mixture, which was protected from light. The suspension was stirred at rt for 1 h, then concentrated. The residue was taken up in CH2Cl2 and washed three times with sat aq KI, then with brine. The organic phase was dried and concentrated. The residue was purified by column chromatography (solvent B, 3:1) to give 522 (3.52 g, 80%) as a colourless foam; 1H NMR: δ 7.15 (m, 25H, Ph), 5.50 (dd, 1H, H-2B), 5.30-5.27 (m, 2H, H-1C, H-2C), 5.23 (d, 1H, J1,2=3.3 Hz, H-1E), 5.18 (dd, 1H, J2,3=3.2, J3,4=10.0 Hz, H-3B), 5.10 (d, 1H, J1,2=1.2 Hz, H-1B), 5.00-4.35 (m, 9H, H-4B, OCH2), 4.28 (dd, 1H, J2,3=3.2, J3,4=8.6 Hz, H-3C), 4.20-4.00 (m, 3H, H-3E, 5E, 5C), 3.80-3.50 (m, 6H, H-2E, 6aE, 6bE, 5B, 4E, 4C), 3.05 (d, 1H, J)H,1=4.0 Hz, OH), 2.09, 1.81, 1.44 (3s, 9H, CH3C═O), 1.37 (d, 3H, J5,6=6.2 Hz, H-6C), 0.95 (d, 3H, J5,6=6.2 Hz, H-6B); 13C NMR: δ 169.9, 169.8, 169.6, 166.2 (4C, C═O), 138.9-127.5 (Ph), 99.8 (C-1B), 97.3 (C-1E), 91.3 (C-1C), 81.7 (C-3E), 80.7 (C-2E), 78.8 (C-3C), 78.1, 78.0 (2C, C-4E, 4C), 76.6, 75.5 (2C, CH2Ph), 74.9 (2C, C-2E, CH2Ph), 73.8 (CH2Ph), 73.3 (2C, C-4B, 5E), 72.9 (C-2B), 71.2 (2C, C-3B, 6E), 67.5 (C-5C), 67.1 (C-5B), 21.0, −20.6, 20.5 (3C, CH3C═O), 18.9 (C-6C), 17.1 (C-6B). FAB-MS for C59H66O18 (1062) m/z 1085 [M+Na]+. Anal. Calcd. for C59H66O18.H2O: C, 65.54; H, 6.34%. Found: C, 65.68; H, 6.41%.
