反应详情

A mixture of (106) (760 mg, 2.38 mmol), silver carbonate (394 mg, 1.4 mmol), and isobutyric acid (442 μL, 4.76 mmol) in chloroform was stirred at room temperature for 24 h. Another batch of silver carbonate (394 mg, 1.4 mmol) and isobutyric acid (442 μL, 4.76 mmol) was added, and the resulting mixture was stirred for another 24 h. After filtration, the filtrate was concentrated and the resulting residue purified by silica gel flash column chromatography, eluting with 10% ethyl acetate/hexane, to afford 560 mg (63%) of the title compound. 1H NMR (CDCl3, 400 MHz): δ 0.94 (d, J=6.8 Hz, 3H), 0.96 (d, J=6.8 Hz, 3H), 1.15 (d, J=7.2 Hz, 3H), 1.17 (d, J=7.2 Hz, 3H), 1.32-1.58 (m, 10H), 2.01 (m, 1H), 2.19 (s, 2H), 2.55 (m, 1H), 3.18 (m, 2H), 3.67 (s, 3H), 5.33 (t, 1H), 6.56 (d, J=4.8 Hz, 1H). MS (ESI) m/z 372.38 (M+H+).

1. stirringthe resulting mixture was stirred for another 24 h
2. filtrationAfter filtration
3. concentrationthe filtrate was concentrated
4. customthe resulting residue purified by silica gel flash column chromatography
5. washeluting with 10% ethyl acetate/hexane