187662-09-5Relevant articles and documents
Photolabile Ru Model Complexes with Chelating Diimine Ligands for Light-Triggered Drug Release
Battistin, Federica,Balducci, Gabriele,Wei, Jianhua,Renfrew, Anna K.,Alessio, Enzo
, p. 1469 - 1480 (2018)
A series of water-soluble photolabile model complexes of the general formula [Ru([9]aneS3)(chel)(py)]Cl2 ([9]aneS3 = 1,4,7-trithiacyclononane, chel = chelating diimine) was prepared and fully characterized. The phototriggered release of pyridine with visible light as a function of the nature of the diimine {chel = 2,2′-bipyridine (6) 1,10-phenanthroline (7), 4,7-diphenil-1,10-phenanthroline (8), dipyrido-[3,2-a:2′,3′-c]phenazine (dppz, 9), 2,2′-biquinoline (bq, 10)} was investigated. Our aim is to establish whether this type of complexes might be realistically used in the photo-uncaging strategy of photoactivated chemotherapy (PACT) in the future. Compounds 6–9 present a MLCT absorption in the blue region of the visible spectrum. When irradiated with light at 470 nm, they rapidly and quantitatively release the coordinated pyridine. Complex 10 turned out to be quite different from the others in the series. Structure-wise, in 10 the average plane of coordinated bq – owing to its steric demand – is remarkably tilted relative to the equatorial coordination plane [37.43(4)°, with the “front“ of the ligand pointing towards the axial py] and the orientation of py is nearly orthogonal compared to that found in 6 and 7 for minimizing steric clashes with bq. The low-lying acceptor orbitals of bq induce a red-shift of the MLCT absorption maximum to ca. 500 nm. Contrary to the expectations, complex 10 is more photostable compared to 6–9 and photo-dissociation of both py and bq, in nearly equal amounts, occurs. A detailed theoretical investigation was performed on 10 (and on 6 for comparison), for explaining its peculiar spectral features and photochemical behavior.
Structural characterisation of RuII [9]aneS3 polypyridyl complexes by NMR spectroscopy and single crystal X-ray diffraction
Goodfellow, Brian J.,Felix, Victor,Pacheco, Sara M. D.,Pedrosa De Jesus, Julio,Drew, Michael G. B.
, p. 393 - 401 (2008/10/09)
The synthesis of a series of RuII complexes with the thioether ligand [9]aneS3 and various polypyridyl ligands was carried out using [Ru(dmso)4Cl2] as a starting material. The first synthetic step involved the introduction of the thioether ligand and the isolation of the compound [Ru([9]aneS3)(dmso)Cl2]. The polypyridyl ligands were then exchanged to give a series of complexes [Ru([9]aneS3)(X)(Cl]+ (X = 1,10-phenanthroline (phen), 2,2′-bipyridyl (bpy), 4,4′-diphenyl-2,2′,-bipyridyl (dbp) and 4,7′-diphenyl-1,10-phenanthroline (dip)). These complexes were characterised by NMR and UV spectra. The complexes with X = phen and bpy were crystallised and single crystal X-ray diffraction studies carried out. Distorted octahedral coordination geometry was observed for both complexes. The equatorial planes are formed by two macrocyclic sulfur donor atoms and two nitrogen atoms from polypyridyl ligands (bpy or phen). The hexa-co-ordination is achieved via a chlorine and the remaining sulfur, macrocyclic atom. The [9]aneS3 macrocyclic ligand adopts a [333] facial arrangement. The results from NMR studies for [Ru([9]aneS3)(phen)Cl]+ and [Ru([9]aneS3) (bpy)Cl]+ indicate that both complexes exist as two forms in solution with CS symmetry consistent with a [333] facial arrangement. Copyright 1996 Elsevier Science Ltd.
