Synthesis and reactions of 4‐benzoyl‐1,5‐diaryl‐1 H ‐pyrazole‐3‐carbonyl chlorides with various semi‐ and thiosemicarbazides

The 1 H ‐pyrazole‐3‐carboxylic acids 2 were converted via reactions of their acid chlorides 3 with some semi‐ and thiosemicarbazide derivatives into the corresponding new phenylsemi‐ and thiosemicarbazides 4a , 4b , 4c , 4d , 4e , 6 , 5‐(pyrazol‐3‐yl)‐4 H ‐1,2,4‐triazol‐3‐thiones 5a , 5b , and 2‐(pyrazol‐3‐yl)‐1,3,4‐thiadiazol 7 derivatives, in good yields (45‐97%, respectively). The reactions of 4a , 4c , 4e with Lawesson reagent lead to the products 6 and 7 formation. The structures of these newly synthesized compounds were determined from the IR, 1 H‐ and 13 C‐NMR spectroscopic data and elemental analyses. J. Heterocyclic Chem., (2010).