title: Synthesis, characterization, and linkage isomerism in mononuclear ruthenium complexes containing the new pyrazolate-based ligand Hpbl.
abstract: A new tetradentate dinucleating ligand [1,1'-(4-methyl-1H-pyrazole-3,5-diyl)bis(1-(pyridin-2-yl)ethanol)] (Hpbl) containing an O/N mixed donor set of atoms has been synthesized and characterized by analytical and spectroscopic techniques. The Ru-Cl and Ru-aqua complexes containing this ligand of general formula [Ru(II)X(Hpbl)(trpy)](y+) (trpy = 2,2':6',2″-terpyridine; X = Cl, y = 1; X = H2O, y = 2) have been prepared and thoroughly characterized by spectroscopic and electrochemical techniques. The Ru-aqua complex 2 undergoes N → O linkage isomerization as observed electrochemically, and the related thermodynamic and kinetic parameters are extracted from cyclic voltammetry experiments together with DIGISIM, a CV simulation package. Under basic conditions an additional isomer is observed where the pyrazolyl group in the Hpbl ligand is replaced by the geminal pyridyl group. Further structural and electronic characterization of all the isomers has been carried out by means of DFT calculations.
authors: Institute of Chemical Research of Catalonia (ICIQ) , Avingunda Països Catalans 16, E-43007 Tarragona, Spain.
authors: Laia
authors: L
authors: Francàs
authors: Rosa M
authors: RM
authors: González-Gil
authors: Albert
authors: A
authors: Poater
authors: Xavier
authors: X
authors: Fontrodona
authors: Jordi
authors: J
authors: García-Antón
authors: Xavier
authors: X
authors: Sala
authors: Lluís
authors: L
authors: Escriche
authors: Antoni
authors: A
authors: Llobet