反应详情

A stirred solution of methyl 3-[(dipropylamino)carbonyl]-5-(5-methyl-1,2,4-oxadiazol-3-yl)benzoate (629 mg, 1.8 mmol) and lithium iodide (2.4 g, 18 mmol) in pyridine (7 ml) is refluxed for 18 h. The reaction mixture is cooled to room temperature and the solvent is concentrated under reduced pressure. The residue is dissolved in water, washed with ethyl acetate, the aqueous layer is acidified to pH 3 with 1 N hydrochloric acid and extracted with chloroform (3×100 mL). The organic layer is dried (sodium sulfate), filtered, and concentrated to give the title compound. 1H NMR (500 MHz, CDCl3) δ 11.11 (br s, 1H), 8.85 (t, J=1 Hz, 1H), 8.31 (t, J=1 Hz, 1H), 8.23 (t, J=1 Hz, 1H), 3.51 (s, 2H), 3.19 (s, 2H), 2.72 (s, 3H), 1.73 (d, J=7 Hz, 2H), 1.56 (d, J=7 Hz, 2H), 1.01 (t, J=7 Hz, 3H), 0.76 (t, J=7 Hz, 3H).

1. concentrationthe solvent is concentrated under reduced pressure
2. dissolutionThe residue is dissolved in water
3. washwashed with ethyl acetate
4. extractionextracted with chloroform (3×100 mL)
5. dry with materialThe organic layer is dried (sodium sulfate)
6. filtrationfiltered
7. concentrationconcentrated