反应详情

A solution of (N′-benzoyl-hydrazino)-oxo-acetic acid ethyl ester (508 mg, 2.15 mmol) in POCl3 (4 mL) was heated to reflux for 3 hrs. The reaction mixture was then concentrated under reduced pressure to remove POCl3 and the resulting residue was dissolved in ethyl acetate. Subsequently, the ethyl acetate layer was washed with water and brine solution, dried over sodium sulphate and concentrated under reduced pressure to afford 450 mg (96.2% yield) of 5-phenyl[1,3,4]oxadiazole-2-carboxylic acid ethyl ester as off white solid. LCMS purity: 93.86%

1. temperatureto reflux for 3 hrs
2. concentrationThe reaction mixture was then concentrated under reduced pressure
3. customto remove POCl3
4. dissolutionthe resulting residue was dissolved in ethyl acetate
5. washSubsequently, the ethyl acetate layer was washed with water and brine solution
6. dry with materialdried over sodium sulphate
7. concentrationconcentrated under reduced pressure