9-Benzyl-9-aza-tricyclo[5.3.1.02,6]undec-3-ene (6.7 g, 28 mmol) and N-methyl morpholine N-oxide (3.45 g, 29.5 mmol) were stirred in acetone (50 mL) and H2O (2 mL). To this was added osmium tetroxide (OSO4, 1 mL of a 15 mol % t-butanol solution) and the mixture was stirred vigorously. After 7 h, the yellow solution was treated with a slurry of florisil in H2O (5 g in 4 mL) and NaHSO3 (2 g). After 1 h, the slurry was filtered through a Celite™ pad and concentrated. The residue was azeotropically dried by the addition of methanol and concentration in vacuo twice, the second time with silica gel, and the residue dry packed on silica gel (3×5 inch) and eluted with 50% EtOAc/hexane to generate pure product as an oil that crystallizes on standing (6.2 g, 80%). (TLC EtOAc Rf 0.66); 1H NMR (400 MHz, CDCl3) δ 7.30–7.20 (m, 3H), 7.16 (d, J=6.8 Hz, 2H), 4.38 (m, 2H), 3.34 (AB q, ΔAB=26.5, J=12.6 Hz, 2H), 2.83–2.73 (m, 2H), 2.65 (d, J=10.9 Hz, 1H), 2.43 (s, 1H), 2.37 (s, 1H), 2.22 (dd, J=11.3, 1.3 Hz, 1H), 2.13 (dd, J=10.9, 1.5 Hz, 1H), 2.01 (d, J=6.2 Hz, 1H), 1.97–1.87 (m, 2H), 1.75 (m, 1H), 1.57 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 139.4, 129.2, 128.1, 127.1, 80.3, 73.7, 63.1, 56.0, 55.4, 51.9, 43.3, 42.3, 35.2, 34.1, 30.6; GCMS m/z 273 (M)+, 256 (M−OH)+.
