反应详情

A solution of potassium hydroxide (24.6 g, 375 mmol) in H2O (400 ml) was added to a solution of 1-benzyl 4-ethyl 5-oxo-1,4-azepanedicarboxylate (40.0 g, 125 mmol) in ethanol (400 ml). The resulting mixture was heated at reflux for 2.5 hours. Reaction was then cooled to rt., the ethanol was removed under reduced pressure, and was diluted with 200 ml brine and 300 ml ethyl acetate. The layers were separated, and the aqueous phase was extracted with ethyl acetate (2×100 ml). The combined organic layers were washed with brine, dried over MgSO4, and concentrated to an orange oil in vacuo. The product was isolated by flash chromatography (silica gel, 40% EtOAc/hexane) yielding a clear, colorless oil (22.6 g, 73%). 1H NMR (CDCl3) δ 7.31-7.30, 5.12, 3.65-3.63, 2.68-2.60, 1.81-1.78; IR (liq.) 1698, 1475, 1454, 1442, 1423, 1331, 1320, 1295, 1270, 1241, 1191, 1165, 1091, 900, 699 cm−1.

1. temperatureThe resulting mixture was heated
2. temperatureat reflux for 2.5 hours
3. customReaction
4. custom, the ethanol was removed under reduced pressure
5. additionwas diluted with 200 ml brine and 300 ml ethyl acetate
6. customThe layers were separated
7. extractionthe aqueous phase was extracted with ethyl acetate (2×100 ml)
8. washThe combined organic layers were washed with brine
9. dry with materialdried over MgSO4
10. concentrationconcentrated to an orange oil in vacuo
11. customThe product was isolated by flash chromatography (silica gel, 40% EtOAc/hexane)