Reaction Steps
A solution of alcohol 11 (0.439 g, 0.89 mmol) and pyridine (0.25 g, 3.21 mmol) in CH2Cl2 (approximately 5 mL) was added to a solution of 4-nitrophenyl chloroformate (0.30 g, 1.49 mmol) in CH2Cl2 (25 mL) at room temperature, and the reaction mixture was stirred for 20 minutes at room temperature. Solvent was evaporated under reduced pressure, and the residue was separated by chromatography (Hex:ExOAc 4:1+1.5% of Et3N) to provide 0.317 g (0.48 mmol 80%) of 12 as and 0.113 g (0.23 mmol) of starting 11. 1H NMR: 8.25 (d, J=8.8 Hz, 2H) 7.65 (dd, J=8.4, 2.0 Hz, 2H), 7.35, (d, J=9.2, 2H), 6.92-6.82 (m, 4H), 4.43 (t, J=4.4 Hz, 2H), 4.19 (t, J=6.4 Hz, 2H), 3.98 (t, J=4.4 Hz, 2 H), 3.92 (m, 7H), 3.22 (d, J=10.8 Hz, 2H), 2.43 (d, J=10.8 Hz, 2H), 1.75 (p, J=7.2 Hz, 2H), 1.51 (six, J=7.6 Hz, 2H), 1.21 (s, 3H), 1.19 (s, 3H), 0.98 (t, J=7.2 Hz, 3H); 13C NMR: 159.9, 159.2, 155.7, 152.7, 150.0 147.4, 145.6, 131.77, 131.63, 125.5, 124.6, 123.4, 122.0, 119.8, 119.1, 116.25, 116.19, 112.2, 112, 15, 84.1, 79.4, 70.0, 69.1, 68.4, 70.0, 67.8, 37.1, 31.5, 30.8, 22.87, 22.79, 19.5, 14.1.
