Research Information System
HETEROCYCLIC COMMUNICATIONS, vol.11, pp.223-234, 2005 (SCI-Expanded)
The 1H-pyrazole-3-carboxylic acid 2 is obtained easily from the furan-2,3-dione 1 and phenylhydrazine and converted via reactions to its acid chloride 3 which reacts with various binucleophiles; diamine derivatives 4a-i and gives the corresponding 1H-pyrazole-3-carboxamides and 3-carboxylates 5a-i in good yields (50-90 %). The structures of all new synthesized compounds were determined with the C-13 NMR, H-1 NMR, IR, MS spectroscopic data and elemental analyses. Most of them were compared with their previously obtained analogues. The electronic structures of the reactants, their transition states, intermediate states and final products of the reactions were investigated on the base of the AM1 method.