反应详情

A mixture of 1.13 g (3.66 mmol) of 3-(2, 3-dimethoxyphenyl) octanoic acid ethyl ester and 3 ml of 60% nitric acid was stirred at room temperature for 2 hours. The reaction mixture was mixed with water and extracted with ethyl acetate. The organic layer was washed with saturated saline, dried over anhydrous magnesium sulfate and the solvent evaporated in vacuo. The residue was chromatographed on a silica gel column, eluting with ethyl acetate/hexane (1/5) to give 1.15 g of 3-(2, 3-dimethoxy-5-nitropheyl) octanoic acid ethyl ester as a yellow oil. Yield, 89%. This compound showed a coupling constant of J=2.6 Hz in 1H NMR (CDCl3) spectra, suggesting meta-coupling. Further, 0.10 g of 3-(2, 3-dimethoxy-6-nitrophenyl) octanoic acid etheyl ester (yield, 7.7%) was obtained, showing a coupling constant of J=9.1 Hz in 1H NMR (CDCl3) spectra.

1. extractionextracted with ethyl acetate
2. washThe organic layer was washed with saturated saline
3. dry with materialdried over anhydrous magnesium sulfate
4. customthe solvent evaporated in vacuo
5. customThe residue was chromatographed on a silica gel column
6. washeluting with ethyl acetate/hexane (1/5)