反应详情

A mixture of 5-bromo-2-methyl-2,3-dihydro-1-benzofuran (1.0 g, 4.72 mmol), CH3SO2Na (730 mg, 7.08 mmol), L-proline (110 mg, 0.94 mmol), K2CO3 (120 mg, 0.94 mmol) and CuI (89 mg, 0.47 mmol) in DMSO (10 mL) was irradiated at 140° C. for 2 h under microwave. The mixture was extracted with EtOAc (2×30 mL). The combined organic layers were washed with brine (30 mL), dried over Na2SO4, filtered and concentrated to give the crude product that was purified by column chromatography on silica gel (PE/EA=2/1) to give the title compound (500 mg, 50%). 1H NMR (CDCl3, 400 MHz) δ 7.71-7.70 (m, 2H), 6.86-6.82 (m, 1H), 5.08-5.03 (m, 1H), 3.41-3.35 (m, 1H), 3.02 (s, 3H), 2.89-2.83 (m, 1H), 1.56 (d, J=6.4 Hz, 3H).

1. customwas irradiated at 140° C. for 2 h under microwave
2. extractionThe mixture was extracted with EtOAc (2×30 mL)
3. washThe combined organic layers were washed with brine (30 mL)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated
7. customto give the crude product that
8. customwas purified by column chromatography on silica gel (PE/EA=2/1)