Reaction Steps
NaHMDS (1 M solution in THF-heptanes, 1.8 mL, 1.8 mmol) was slowly added to a solution of 11 (320 mg, 0.75 mmol) in dry THF (20 mL) at −78° C. The reaction mixture was stirred at −78° C. for 1 h, and then a solution of phenylselenyl chloride (216 g, 1.13 mmol) in dry THF (5 mL) was added dropwise and the mixture was stirred at −78° C. for 2 h. The reaction mixture was allowed to warm to room temperature and stirred at this temperature for 3 h. The reaction mixture was quenched by slow addition of 1N HCl (5 mL) at 0° C., diluted with water (50 mL) and extracted with chloroform (4×50 mL). The combined extracts were washed with water and brine, dried with sodium sulfate, and evaporated under reduced pressure. The residue was dissolved in THF (10 mL). Acetic acid (1 mL) and hydrogen peroxide (30%, 5 mL) were added sequentially at 0° C. The reaction mixture was warmed to room temperature and stirred for 6 h. Saturated aqueous sodium bicarbonate (5 mL) was added to the mixture at 0° C. Chloroform (3×10 mL) was used to extract the product. The combined extracts were washed with water and brine, dried with sodium sulfate, and evaporated to afford the product (198 mg, 62%): mp 165-170° C. IR (film) 1730, 1718, 1638 cm−1; 1H NMR (500 MHz, CDCl3) δ 8.05 (d, J=6.2 Hz, 1 H), 7.86 (s, 1 H), 7.49 (t, J=7.9 Hz, 1 H), 7.22-7.16 (m, 2 H), 7.16-7.11 (m, 1 H), 6.53 (s, 1 H), 4.04 (s, 3 H), 3.99 (s, 3 H), 3.72 (s, 3 H), 3.45 (s, 3 H), 3.24 (s, 3 H); 13C NMR (126 MHz, CDCl3) δ 167.39, 162.03, 154.22, 154.07, 150.14, 139.65, 136.41, 130.97, 129.29, 128.59, 124.49, 119.35, 112.69, 108.14, 104.80, 56.52, 56.37, 52.75, 52.26, 33.18; ESIMS m/z (rel intensity) 449 (18), 427 (MH+, 100), 395 (78); ESIHRMS m/z MH+ calcd. for C22H22N2O7, 427,1505; found, 427.1507.
