774219-52-2Relevant academic research and scientific papers
Ruthenium complexes of easily accessible tridentate ligands based on the 2-aryl-4,6-bis(2-pyridyl)-s-triazine motif: Absorption spectra, luminescence properties, and redox behavior
Polson, Matthew I. J.,Medlycott, Elaine A.,Hanan, Garry S.,Mikelsons, Larisa,Taylor, Nick J.,Watanabe, Masashi,Tanaka, Yasutaka,Loiseau, Frederique,Passalacqua, Rosalba,Campagna, Sebastiano
, p. 3640 - 3648 (2004)
A family of tridendate ligands 1a-e, based on the 2-aryl-4,6-di(2-pyridyl)- s-triazine motif, was prepared along with their hetero- and homoleptic Ru II complexes 2a-e ([Ru(tpy)(1a-e)]2+; tpy = 2,2′:6′,2″-ter-pyridine) and 3a-e ([(Ru(1a-e) 2]2+), respectively. The ligands and their complexes were characterized by 1H NMR spectroscopy, ES-MS, and elemental analysis. Single-crystal X-ray analysis of 2a and 2e demonstrated that the triazine core is nearly coplanar with the non-coordinating ring, with dihedral angles of 1.2 and 18.6°, respectively. The redox behavior and electronic absorption and luminescence properties (both at room temperature in liquid acetonitrile and at 77 K in butyronitrile rigid matrix) were investigated. Each species undergoes one oxidation process centered on the metal ion, and several (three for 2a-e and four for 3a-e) reduction processes centered on the ligand orbitals. All compounds exhibit intense absorption bands in the UV region, assigned to spin-allowed ligand-centered (LC) transitions, and moderately intense spin-allowed metal-to-ligand charge-transfer (MLCT) absorption bands in the visible region. The compounds exhibit relatively intense emissions, originating from triplet MLCT levels, both at 77 K and at room temperature. The incorporation of triazine rings and the near planarity of the noncoordinating ring increase the luminescence life-times of the complexes by lowering the energy of the 3MLCT state and creating a large energy gap to the dd state.
Non-covalent polymerisation in the solid state: Halogen-halogen vs. methyl-methyl interactions in the complexes of 2,4-di(2-pyridyl)-1,3,5-triazine ligands
Medlycott, Elaine A.,Udachin, Konstantin A.,Hanan, Garry S.
, p. 430 - 438 (2008/01/27)
Fe(ii), Co(ii), Ni(ii) and Cu(ii) complexes based on the triazine ligand 2,4-di(2′-pyridyl)-6-(p-bromo-phenyl)-1,3,5-triazine have been synthesised and characterised. The electrochemical, magnetic and spectroscopic properties of the complexes have also been investigated, and the electron deficient triazine ligand has been shown to affect each of these properties. Further investigation of solid state structures of the ligand and its Fe(ii), Co(ii) and Cu(ii) complexes has established that stabilising Br-Br interactions exist which link neighbouring molecules to form one-dimensional tapes. A slight modification of the ligand, i.e., using 2,4-di(2′-pyridyl)-6-(p- methylphenyl)-1,3,5-triazine, in which the phenyl substituent has changed from a bromine to a methyl group, eliminates the one-dimensional tape and gives rise to significant π-stacking interactions in the solid state. The Royal Society of Chemistry.
