Homoleptic Ru(II) complex with terpyridine ligands appended with terthiophene moieties: Synthesis, characterization and electropolymerization
作者:Roberta Scanu、Paola Manca、Antonio Zucca、Gavino Sanna、Nadia Spano、Renato Seeber、Chiara Zanardi、Maria I. Pilo
DOI:10.1016/j.poly.2012.09.056
日期:2013.1
A new Ru(II) complex, [Ru(TTT)(2)][PF6](2) (TTT = 4'-[(2,2':5',2 ''-terthien-3'-yl)methoxy]-2,2':6',2 ''-terpyridine) has been synthesized and characterized by H-1 NMR and UV-Vis spectroscopy and by cyclic voltammetry. The electrosynthesis of the corresponding conductive polymer, P[Ru(TTT)(2)], is reported, as well as its voltammetric and spectroelectrochemical characterization. The comparison between [Ru(TTT)(2)][PF6](2) and TTT voltammetric data shows that the presence of the metal ion makes easier the oxidation and the polymerization of the organic framework. On the other hand, UV-Vis data confirm that the presence of the -O-CH2- spacer between coordinating and polymerizing unit (terpyridine and terthiophene, respectively) reduces the electronic delocalization among these moieties, analogously to that observed in the TTT ligand alone. As far as P[Ru(TTT)(2)] is concerned, the voltammetric characterization evidences the so-called 'charge-trapping' phenomena, already observed also in PTIT, too. Moreover, spectroelectrochemical characterization shows a likely overlapping of the pi-pi* polymer and MLCT complex absorption bands, causing a bathochromic shift with respect to PTTT. (c) 2012 Elsevier Ltd. All rights reserved.