A mixture of 2.2 mmol 2-bromo-5-trifluoromethyl-[1,3,4]thiadiazole (CA 37461-6-3; prepared according to DE2533605), 2.3 mmol piperazine-1-carboxylic acid tert-butyl ester and 4.3 mmol potassium carbonate in 10 ml acetonitrile was refluxed for 4 hours. The reaction mixture was cooled, poured into water and extracted 3 times with ethyl acetate. Concentration and recrystallisation of the crude material from diethyl ether yielded the title compound as a colorless solid. MS (m/e): 397.2 ([M+CH3COO]31 , 100%).
