反应详情

A solution of methyl 5-((hydroxyimino)methyl)thiophene-2-carboxylate (440 mg, 2.4 mmol) in acetic anhydride (10 mL) was refluxed for 16 h. After completion, the reaction mixture was cooled to room temperature, concentrated under reduced pressure and the residue was dissolved in diethyl ether. The organic layer was washed with 10% aqueous NaOH solution, water and brine, and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure to yield methyl 5-cyanothiophene-2-carboxylate (5-cyano-thiophene-2-carboxylic acid methyl ester) (400 mg, yield 90%) which was carried through without any further purification. 1H NMR (400 MHz, DMSO-d6) δ 7.77 (d, J=4.2 Hz, 1H), 7.60 (d, J=4.1 Hz, 1H), 3.95 (s, 3H).

1. concentrationconcentrated under reduced pressure
2. dissolutionthe residue was dissolved in diethyl ether
3. washThe organic layer was washed with 10% aqueous NaOH solution, water and brine
4. dry with materialdried over anhydrous sodium sulfate
5. customThe solvent was removed under reduced pressure