反应详情

A solution of ethyl 2-amino-2-cyanoacetate (0.20 g, 1.56 mmol) and triethyl formate (0.30 mL, 1.72 mmol) in acetonitrile (5 mL) was refluxed for 1 h. After concentrating the residue was dissolved in a solution of acetonitrile (5 mL) and n-butylamine (0.17 mL, 1.72 mmol). The resulting mixture was stirred at reflux for 1 h. The solvents were removed under reduced pressure and the residue was partitioned between water and ethyl acetate. The organic layer was separated and washed with brine and dried (Na2SO4). After removing the solvent under reduced pressure, flash chromatography (1:1 ethyl acetate/hexane) of the residue gave 0.12 g, 40% of the title compound as an oil: 1H NMR (250 MHz, CDCl3)δ 6.97 (s, 1H), 5.10 (s, 2H), 4.31 (q, 2H), 3.75 (t, 2H), 1.65 (m, 2H), 1.35 (m, 5H), 0.97 (t, 3H); MS(ESI) m/e 212.2 [M+H]+.

1. concentrationAfter concentrating the residue
2. temperatureat reflux for 1 h
3. customThe solvents were removed under reduced pressure
4. customthe residue was partitioned between water and ethyl acetate
5. customThe organic layer was separated
6. washwashed with brine
7. dry with materialdried (Na2SO4)
8. customAfter removing the solvent under reduced pressure, flash chromatography (1:1 ethyl acetate/hexane) of the residue