反应详情

温度

70 °C

To a solution of methyl 3-hydroxy-4-methoxy benzoate (2.0 g, 11 mmol) in DMF (25 mL) was added cesium carbonate (7.2 g, 22 mmol) and 1,1-dimethylethyl 4-{[(methylsulfonyl)oxy]methyl}piperidine-1-carboxylate (3.2 g, 11 mmol). The mixture was heated to 70° C. and stirred for 2 h. After cooling to rt, water was added and the resulting aqueous mixture was extracted with ether followed by ethyl acetate. The organic layers were combined, dried over sodium sulfate, filtered, and concentrated in vacuo. The crude residue was purified by flash chromatography (70% hexanes, 30% ethyl acetate) to provide 3.54 g of 1,1-dimethylethyl 4-[({2-(methyloxy)-5-[(methyloxy)carbonyl]phenyl}oxy)methyl]piperidine-1-carboxylate (9.3 mmol, 85% yield). 1H NMR (400 MHz, CDCl3): δ7.69-7.66 (dd, 1H), 7.52 (d, 1H), 6.88 (d, 1H), 4.15 (br m, 2H), 3.92 (s, 3H), 3.91-3.88 (m, 2H), 3.90 (s, 3H), 2.76 (br m, 2H), 2.06 (m, 1H), 1.88 (br d, 2H), 1.47 (s, 9H), 1.31-1.25 (m, 2H); MS (EI) for C20H29NO6: 402 (MNa+).

1. temperatureAfter cooling to rt
2. extractionthe resulting aqueous mixture was extracted with ether
3. dry with materialdried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe crude residue was purified by flash chromatography (70% hexanes, 30% ethyl acetate)