New 3-(2-pyridyl)-1,2,4-triazole derivatives and their palladium (II) complexes

Abstract

The article is devoted to investigation of coordination compounds of palladium (II) with 3-(2-pyridyl)-1,2,4-triazole derivatives containing amino groups. We syntesized 4 ligands and 4 new coordination compounds. An interesting after removing of BOC-protection, NH2-group is still uncoordinated. In 1H NMR spectra of complexes was a significant shift of the ortho-pyridine proton in a low-field area, which prove proposed structure. This may be due to its closeness to the lone electron pair of the nitrogen cycle of the second triazole ligand.

Synthesis of 3-(2-Hydroxyphenyl)-5-(2-Pyridinyl)-1,2,4-triazoles as a potential chelate ligand for Uranyl ion

“…Compounds H4L 1 and H5L 2 were obtained by acylation of triazolylcarboxylic acid hydrazides by picolinic acid iminoester, with subsequent cyclization providing title compounds (Scheme 1), which is a common method for the preparation of 1,2,4-triazoles [11,12]. The first step of the reaction proceeds is coordinated in the anionic form [13,14]. The obtained complexes, especially [(UO2)(H3L 2 )](СH3OH), so are poorly soluble in DMSO or other solvents, and therefore we were unable to obtain a suitable for analysis 13 C NMR spectrum for [(UO2)(H2L 1)](СH3OH)…”