Syntheses and photophysical properties of N-pyridylimidazol-2-ylidene tetracyanoruthenates(II) and photochromic studies of their dithienylethene- containing derivatives

Abstract

A series of tetracyanoruthenate(II) with chelating pyridyl N-heterocyclic carbene ligands (NHC-py) was synthesized and characterized. Their photophysical and electrochemical properties as well as the photochromic behavior of their dithienylethene-containing complexes were studied. Photocyclization was found to take place upon irradiation into the metal-to-ligand charge transfer (MLCT) absorption bands of these complexes, and evidence is provided to support the triplet-sensitizing reaction pathway. Enlightening chemistry: Luminescent tetracyanoruthenates(II) with chelating pyridyl N-heterocyclic carbene ligands have been synthesized and their dithienylethene-containing complexes have been shown to display interesting photochromic properties (see figure). © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.