反应详情

To a suspension of hydrazine hydrochloride (10 g, 146.66 mmol) in ethanol (500 mL) at −20° C. was added DIPEA (45.3 mL, 266.66 mmol) followed by stirring at this temperature for 10 minutes. Ethyl (2Z)-2-(ethoxymethylene)-4,4,4-trifluoro-3-oxobutanoate (Preparation 113, 32 g, 133.33 mmol) was added and the reaction stirred at room temperature for 18 hours. The reaction was concentrated in vacuo and diluted with EtOAc. The organic solution was washed with water, dried over sodium sulphate and concentrated in vacuo. The residue was purified using silica gel column chromatography eluting with 30% EtOAc in hexane to afford the title compound (13 g) that was taken directly on to the next step.

1. stirringthe reaction stirred at room temperature for 18 hours
2. concentrationThe reaction was concentrated in vacuo
3. additiondiluted with EtOAc
4. washThe organic solution was washed with water
5. dry with materialdried over sodium sulphate
6. concentrationconcentrated in vacuo
7. customThe residue was purified
8. washeluting with 30% EtOAc in hexane