反应详情

Sodium iodide (10.6 g, 71 mmol) was added to a green solution of 2a (4.26 g, 14 mmol) in acetonitrile (80 mL) in a vessel covered with aluminum foil to protect from light, followed by chlorotrimethylsilane (8.9 mL, 71 mmol) and water (0.4 mL, 21 mmol). The yellow-orange mixture was refluxed overnight in the dark. HPLC analysis showed that although some starting pyridine was still present, decomposition also appeared to be occurring. The reaction was quenched with saturated sodium thiosulfate solution (30 mL). The resulting mixture was extracted with ethyl acetate (3×50 mL). The combined organic layer was washed with brine (30 mL), dried over sodium sulfate, and concentrated to give a yellow oil. The oil was purified by SiO2 chromatography (120 g), loaded with CH2Cl2 and eluted using a gradient of ethyl acetate in hexanes to afford 136a (2.34 g, 58% yield) as a yellow waxy solid, HPLC purity 100%, 3.66 min (Method A); [M+H]+=289.17; in 1H NMR (500 MHz, CDCl3) δ ppm 8.42 (d, 1H, J=5.0 Hz), 7.48 (m, 1H), 7.18 (m, 2H), 6.92 (m, 1H), 6.33 (d, 1H, J=10.0 Hz), 1.37 (s, 9H); 13C (125 MHz, CDCl3) δ (ppm), 163.87, 155.70, 150.61, 142.05, 139.87, 127.86, 126.83, 125.98, 122.98, 104.62, 34.68, 30.17.

1. temperatureThe yellow-orange mixture was refluxed overnight in the dark
2. customThe reaction was quenched with saturated sodium thiosulfate solution (30 mL)
3. extractionThe resulting mixture was extracted with ethyl acetate (3×50 mL)
4. washThe combined organic layer was washed with brine (30 mL)
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated
7. customto give a yellow oil
8. customThe oil was purified by SiO2 chromatography (120 g)
9. washeluted