Ethyl Thioglycolate → 3-Amino-4-cyano-5-trifluoromethyl-thiophene-2-carboxylic acid ethyl ester

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Reaction Steps

Combine 1,1-dicyano-2-chloro-2-(trifluoromethyl)ethylene (0.554 mmol) (prepared by the method of Middleton, J. Fluorine Chem., 20, 1982, p 397-418) and ethanol in a 50 ml flask. Add ethyl 2-mercaptoacetate (0.554 mmol) and potassium acetate (0.831 mmol) and heat to 60-70° C. for 30-40 minutes. Cool the reaction and add water. Product crystallizes as yellowish needles. Filter crystals and wash with 1:1 ethanol/water. Dry solid under reduced pressure to give the title compound as light yellow crystals: 1H NMR (400 MHz, CDCl3) δ 5.88 (s, 2H), 4.36 (q, 2H, J=7.2 Hz), 1.38 (t, 3H, J=7.0 Hz), MS found (M−1) 262.9.

Provenance & Evidence