2134/25415
Edwin C. Constable
Edwin C.
Constable
Catherine E. Housecroft
Catherine E.
Housecroft
Peter Kopecky
Peter
Kopecky
Colin J. Martin
Colin J.
Martin
Iain Wright
Iain
Wright
Jennifer A. Zampese
Jennifer A.
Zampese
Investigating the effects of supramolecularly caging ligands in [Ru(bpy)2L]2+ complexes
Loughborough University
2017
Ruthenium(II)
Bipyridine
Crystal structure
Electrochemistry
Photophysics
Absorption spectroscopy
Chemical Sciences not elsewhere classified
Inorganic Chemistry
2017-06-16 08:24:29
Journal contribution
https://repository.lboro.ac.uk/articles/journal_contribution/Investigating_the_effects_of_supramolecularly_caging_ligands_in_Ru_bpy_2L_2_complexes/9395705
Five ruthenium(II) complexes [Ru(bpy)2(L)][PF6] 2 in which L is a 6-substituted 2,2′-bipyridine ligand (ligands 1-3), 5-(2-picoloyl) (4), or an N,O-donor (5) have been prepared and characterized to investigate the role of the intramolecular caging effect of pendant aryl-substituents on the electronic and photophysical properties. The single crystal structures of three of the complexes are reported; in [Ru(bpy)2(L)][PF6]2 where L = 6-(selenophen-2-yl)-2,2′-bipyridine, intra-cation face-to-face π-stacking of the selenophenyl unit and one pyridine ring of an adjacent ligand is observed. In comparison to [Ru(bpy)3]2+, the energy of the MLCT band in [Ru(bpy)2(L)]2+ for L = 1, 2, 3 or 4 is little affected, but a red-shift of 35 nm is observed for [Ru(bpy) 2(5)]2+. The new complexes are emissive at room temperature in degassed MeCN solution; values of λmaxem range from 613 to 689 nm for [Ru(bpy)2(L)]2+ (L = 1 to 5). The electrochemical behaviour of [Ru(bpy)2(L)][PF 6]2 for L = 1, 2 and 3 is similar; in contrast, [Ru(bpy)2(4)][PF6]2 exhibits more complicated ligand-based redox behaviour, and for [Ru(bpy)2(5)][PF 6]2, the presence of the N,O-donor shifts the metal-based oxidation to lower potential. © 2013 Elsevier Ltd. All rights reserved.