Reaction Steps
To a solution of (±)-1-hydroxy-1-(3-carbamylmethoxyphenyl)-2-phenyl-2-(1,3-dithian-2-yl)-ethane (192 mg, 0.5 mmol) in 10 mL THF was added DMAP (2 mg), triethylamine (70 mL, 0.5 mmol), and acetic anhydride (94 mL, 1.0 mmol). The solution was stirred at room temperature for 4 h, and then partitioned between ethyl acetate (50 mL) and 5% sodium bicarbonate (50 mL). The organic phase was washed with water (3×50 mL), dried with Mg2SO4, and evaporated to yield a colorless oil. Yield 205 mg (98%). IR: 3479, 3331 (br), 1747, 1694, 1589, 1443, 1224, 1033, 910, 718 cm-1. 1H NMR (CDCl3, TMS) d 7.740 (dd, J=8.15, 1.55 Hz, 2 H), 7.348-7.281 (m, 3 H), 7.111 (t, J=7.96 Hz, 1 H), 6.801 (dd, J=8.18, 2.53 Hz, 1 H), 6.686 (d, J=7.59Hz, 1 H), 6.521 (s, 2 H), 6.312 (s, 1 H), 6.136 (s, 1 H), 4.238 (s, 2 H), 2.751-2.597 (m, 4 H), 2.104 (s, 3 H), 1.933-1.857 (s, 1 H). 13C NMR (CDCl3, TMS) d 171.080, 169.318, 156.012, 136.974, 130.771, 128.402, 128.045, 127.738, 122.586, 115.072, 114.635, 79.890, 66.982, 63.133, 27.270, 27.109, 24.568, 20.848. Anal. Calcd. for C21H23NO4S2 : C, 60.41; H, 5.55; N, 3.35. Found: C, 59.92; H, 5.76; N, 3.14.
