反应详情

温度

0 °C

To a solution of 1.0 g (10.0 mmol) of tetronic acid in 30 mL of dry N,N-dimethylformamide at 0° C. is added 1.5 mL (11 mmol) of triethylamine followed by 0.37 g (30 mmol) of 4 dimethylaminopyridine. After stirring at 0° C. for 5 minutes, 2.0 g (11.7 mmol) of 4-cyclohexyl butyric acid is added, followed by 2.25 g (11.7 mmol) of 1-(3-dimethylaminopropyl)-3-ethyl carbodiimide. After 10 minutes, the ice bath is removed and the reaction mixture is allowed to stir overnight. The reaction mixture is quenched with 1N HCl and the solution is washed three times with hexanes. The combined organic layers are washed with water, dried over magnesium sulfate and evaporated. The residue is flash chromatographed on silica gel using 5% methanol/ethyl acetate with 2 mL of acetic acid/liter to give an orange solid: m.p. 38-42° C.; IR (film) 2920, 2840, 1770, 1690, 1660, 1600 cm-1 ; NMR (CDCl3) δ 0.9 (m, 2H), 1.2 (m, 6H), 1.7 (m, 6H), 2.9 (q, J=7 Hz, 2H), 4.6 and 4.7 (s, 2H), 12.1 (bs, 1H); MS (EI): M+ 252.

1. waitAfter 10 minutes
2. customthe ice bath is removed
3. stirringto stir overnight
4. customThe reaction mixture is quenched with 1N HCl
5. washthe solution is washed three times with hexanes
6. washThe combined organic layers are washed with water
7. dry with materialdried over magnesium sulfate
8. customevaporated
9. customchromatographed on silica gel using 5% methanol/ethyl acetate with 2 mL of acetic acid/liter
10. customto give an orange solid