Reaction Steps
A batch of the amine 15 (22.5 g, 61.5 mmol) was dissolved in anhydrous DCM (300 mL) in the presence of anhydrous pyridine (10.9 mL, 134 mmol) at 0° C. Allyl chloroformate (7.17 mL, 67.5 mmol) diluted in anhydrous DCM (200 mL) was added dropwise at 0° C. The resulting solution was allowed to stir overnight at room temperature. It was then washed with cold 1N aqueous HCl (200 ml), water (200 mL), saturated aqueous NaHCO3 (200 mL), and brine (200 mL). The solution was then dried (MgSO4), and the solvent was removed in vacuo to provide 16, slightly contaminated by the product of diacylation (27 g, quantitative yield). A sample was columned (EtOAc/Hexane) to provide the analytical data. 1H NMR (CDCl3) δ 8.78 (1H, bs), 7.75 (1H, s), 6.82 (1H, s), 5.97 (1H, m), 5.38-5.34 (1H, dd, J=1.5, 17.2 Hz), 5.27-5.24 (1H, dd, J=1.3, 10.4 Hz, 1H), 4.63 (2H, m), 4.40 (2H, bs), 4.11 (2H, t, J=6.3 Hz), 3.82 (3H, s), 3.69 (4H, m), 3.61-3.49 (2H, m), 2.54 (2H, t, J=7.4 Hz), 2.18 (2H, p, J=6.7 Hz), 1.92-1.70 (4H, m); 13C NMR (CDCl3) δ 173.4, 170.9, 153.6, 150.5, 144.0, 132.5, 132.0, 118.1, 115.4, 111.6, 105.6, 67.7, 66.6, 65.8, 61.1, 60.4, 56.6, 51.7, 30.5, 28.3, 25.1, 24.3; MS (FAB+) m/z 50 (451, M+H); IR (golden gate) vmax 2949, 2359, 1728, 1596, 1521, 1433, 1202, 1173, 1119, 998, 844, 652 cm−1; [α]26D=−67° (c=0.45, CHCl3).
