反应详情

A 50-mL round bottom flask was charged with ethyl (Z)-3-[(3-ethoxy-3-oxo-propanoyl)amino]-2-ethyl-but-2-enoate (540 mg, 2 mmol, 1 eq.), sodium methoxide (750 mg, 6.8 mmol, 3.4 eq. 25 wt. % in MeOH) and EtOH (10 ml). The mixture was stirred under reflux for 1 hr. After cooling to room temperature, the mixture was acidified by addition of 2N HCl aq. (5 ml) and extracted with ethyl acetate (3×10 ml). The combined organic layers were dried over anhydrous sodium sulfate and concentrated on a rotary evaporator to afford crude ethyl 5-ethyl-4-hydroxy-6-methyl-2-oxo-1H-pyridine-3-carboxylate (205 mg, 46% yield) as yellow solid.

1. temperatureunder reflux for 1 hr
2. extractionextracted with ethyl acetate (3×10 ml)
3. dry with materialThe combined organic layers were dried over anhydrous sodium sulfate
4. concentrationconcentrated on a rotary evaporator