Ethyl 2-(ethoxymethylene)-4,4,4-trifluoroacetoacetate synthesis
- Product Name:Ethyl 2-(ethoxymethylene)-4,4,4-trifluoroacetoacetate
- CAS Number:571-55-1
- Molecular formula:C9H11F3O4
- Molecular Weight:240.18
Yield:571-55-1 97.1%
Reaction Conditions:
with acetic anhydride at 135; for 18 h;
Steps:
1.E E.
Ethyl 2-(ethoxymethylene)-4,4,4-trifluoro-3-oxobutanoate, 1f
Ethyl 4,4,4-trifluoro-3-oxobutanoate (30 g, 162.9 mmol) was added to a solution of triethoxymethane (72.4 g, 488.8 mmol) in acetic anhydride (50 mL).
The mixture was stirred at 135° C. for 18 h.
The brown mixture was concentrated to afford ethyl 2-(ethoxymethylene)-4,4,4-trifluoro-3-oxobutanoate, 1f (38 g, 97.1%) as a brown oil, which was used in the following reaction without further purification. 1H NMR (400 MHz, CDCl3) δ ppm 1.23-1.33 (m, 3H) 1.40 (dt, J=14.18, 7.19 Hz, 3H) 4.19-4.36 (m, 4H) 7.66-7.87 (m, 1H).
References:
US2018/170909,2018,A1 Location in patent:Paragraph 0824; 0825