133046-46-5

354-38-1

70-23-5

133046-46-5

The general procedure for the synthesis of ethyl 2-trifluoromethyl-4-carboxylate thiazole from trifluoroacetamide and ethyl 3-bromopyruvate was as follows: 2,2,2-trifluoroacetamide (14.24 g, 1 eq.) and Lawesson's reagent (30.6 g, 0.6 eq.) were dissolved in THF (120 mL), and the reaction was stirred for 18 hr. under reflux conditions. Upon completion of the reaction, the mixture was cooled, ethyl 3-bromopyruvate (16 mL, 1 eq.) was added, and the reaction was continued under reflux conditions until the end of the week. At the end of the reaction, the reaction mixture was cooled, the solvent was evaporated under vacuum and the crude product obtained was extracted with dichloromethane and washed with water. The organic layer was dried with anhydrous Na2SO4, filtered and concentrated to give an orange colored oil. Purification of the above oil by silica gel column chromatography (eluent: petroleum ether/dichloromethane) afforded the target compound 251 in 40% yield.1H NMR (DMSO-d6, 400 MHz): δ (ppm) 1.32 (t, J = 7.10 Hz, 3H), 4.34 (q, J = 7.10 Hz, 2H), 8.9 (s, 1H); 19F NMR (DMSO-d6, 376 MHz): δ (ppm) -60.29 (s, 3F); MS (ESI, EI+): m/z = 225.9 (MH+).