反应详情

温度

0 °C

Ceric ammonium nitrate (270 mg, 0.498 mmol) was dissolved into H2O (0.75 mL) and AcCN (1.5 mL) and the solution chilled to 0° C. 77.9 mg of (E)-7-(2,5-dimethoxy-3,4,6-trimethylphenyl)-5-methylhept-5-enyl acetate (0.223 mmol) in AcCN (1.5 mL) was added over 2 minutes and the dark orange solution stirred for 0.5 h. H2O (3 mL) and EtOAc (3 mL) were then added, the layers separated and the organics washed 2×2 mL H2O. The combined aqueous phase was back extracted 3×5 mL EtOAc and the combined organics washed 2×5 mL saturated NaCl solution and dried over anhydrous Na2SO4. The resulting yellow liquid was concentrated to a yellow oil and subjected to flash chromatography, which yielded 25.8 mg of (E)-5-methyl-7-(2,4,5-trimethyl-3,6-dioxocyclohexa-1,4-dienyl)hept-5-enyl acetate as a bright yellow oil (36.2%). 1H NMR (400 MHz, CDCl3) d 4.95 (t, J=6.4 Hz, 1H), 4.02 (t, J=6.8 Hz, 2H), 3.19 (d, J=6.8 Hz, 2H), 2.01 (m, 11H), 1.73 (s, 3H), 1.55 (m, 2H) 1.42 (m, 2H). 13C NMR (100 MHz, CDCl3) d 187.9, 187.0, 171.1, 143.0, 140.4, 140.3, 136.7, 119.9, 64.4, 39.1, 28.1, 25.6, 24.1, 20.9, 16.1, 12.3, 12.1.

1. customthe layers separated
2. washthe organics washed 2×2 mL H2O
3. extractionThe combined aqueous phase was back extracted 3×5 mL EtOAc
4. washthe combined organics washed 2×5 mL saturated NaCl solution
5. dry with materialdried over anhydrous Na2SO4
6. concentrationThe resulting yellow liquid was concentrated to a yellow oil