Iodoethane → Ethyl 1-ethyl-3-(trifluoromethyl)-1H-pyrazole-4-carboxylate

Participants

Reaction Steps

Ethyl 3-trifluoromethylpyrazole-4-carboxylate (5 g), potassium carbonate (3.48 g) and ethyl iodide (2.3 ml) in acetonitrile were heated at reflux overnight. After cooling, ethyl acetate and water were added and the organic phase separated. The aqueous layer was extracted with ethyl acetate and the combined organic extracts were dried (magnesium sulphate) and evaporated under reduced pressure to give a yellow oil which was purified by crystallisation in hexane to produce 4-ethoxycarbonyl-1-ethyl-3-trifluoromethylpyrazole as white crystals (3.65 g), 1H NMR (CDCl3) δ1.25(3H,t), 1.45(3H,t), 4.10(2H,q), 4.20(2H,q) 7.90(1H,s) ppm.

Provenance & Evidence