General procedure for the synthesis of 3,5-bis(trifluoromethyl)phenylethynyltrimethylsilane from (3,5-bis(trifluoromethyl)phenylethynyl)trimethylsilane: To a mixed solution of 2-[3,5-bis(trifluoromethyl)phenyl]ethynyltrimethylsilane (83.1g, 267.7mmol) in methanol (70mL) and chloroform (70mL) was added potassium carbonate (7.4g, 53.5 mmol), followed by stirring the reaction mixture at room temperature overnight. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure. Water was added to the residue and extracted with ether. The organic layers were combined, washed with saturated brine and dried over anhydrous sodium sulfate. After filtration to remove the desiccant, the filtrate was concentrated under reduced pressure to give the crude product. The crude product was further purified by reduced pressure distillation (82 °C, 100 mbar) to afford 3,5-bis(trifluoromethyl)phenylacetylene (48.7 g, 76% yield) as a colorless oil. The structure of the product was confirmed by 1H NMR (CDCl3): δ 7.92 (2H, s), 7.84 (1H, s), 3.26 (1H, s).
