Syntheses, Crystal Structures, and Spectral Characterization of Three New Asymmetrical Substituted Triaryltriazoles

Triaryltriazoles are of interest in iron(II) complexes designed to study spin-crossover properties. In this study, three new asymmetrical substituted triaryltriazoles, 3-(p-R-phenyl)-4-(p-chlorophenyl)-5-(2-pyridyl)-1,2,4-triazoles (R = OCH3, 5a; Cl, 5b; Br, 5c), were successfully synthesized from 2-picolinic acid by a three-step reaction through an intermediate N-(p-R-phenylcarbonyl)-N′-(2-pyridylcarbonyl)hydrazine (4a–4c). Yield of 5a–5c is in the range from 74 to 87%. The compounds 5a–5c were characterized by UV, FTIR, 1H-NMR, electrospray ionization mass spectrum spectra, and elemental analysis. Additionally, the absolute configurations of 5a–5c were determined by single crystal X-ray crystallography.