Copper(II) complexes of chiral 1,2,3-triazole biheterocyclic ‘click’ ligands equipped in Cinchona alkaloid moiety

Autor: H. Czapor-Irzabek, Rafał Kowalczyk, K. Lipke, Joanna Gałęzowska, Przemysław J. Boratyński
Rok vydání: 2017
Předmět:
Zdroj: Polyhedron. 121:1-8
ISSN: 0277-5387
Popis: Chiral 1,4-disubstituted-1,2,3-triazole mono- and biheterocyclic ‘click’ ligands derived from Cinchona alkaloids were synthesized using copper(I) catalyzed azide–alkyne cycloaddition (CuAAC) and studied in terms of coordination chemistry towards Cu(II). In broad range of pH the studied ligands form complexes with stoichiometry ML2 in which the coordination involves two neighboring nitrogen atoms from 1,2,3-triazole (N3) and pyridine unit, respectively. The copper(II) coordination is site-selective among studied ligands (L1,2,4) apart for L3, which due to the lack of pyridine next to the triazole moiety and/or possible steric strain in formed complex turned out to be the ligand which metal binding is weaker than others under studied conditions. Thermodynamic analysis which involved potentiometric and calorimetric studies revealed relatively low stability of formed complexes, which binding events are entropy driven processes.
Databáze: OpenAIRE