4-Substituted and 4,5-Disubstituted 3,6-Di(2-pyridyl)pyridazines: Ligands for Supramolecular Assemblies
作者:Edwin C. Constable、Catherine E. Housecroft、Markus Neuburger、Sébastien Reymann、Silvia Schaffner
DOI:10.1002/ejoc.200701114
日期:2008.3
The syntheses by inverse electron demand Diels-Alder reactions and characterization of 28 members of a family of 3,6-di(2-pyridyl)pyridazines, functionalized in the 4- or 4,5-positions are reported. Single crystal structural data are presented for four representative derivatives.
Substituted pyridazines as ligands in homoleptic (fac and mer) and heteroleptic Ru(ii) complexes
作者:Gareth Cooke、Gearóid M. Ó Máille、Roberto Quesada、Longsheng Wang、Sunil Varughese、Sylvia M. Draper
DOI:10.1039/c1dt10340g
日期:——
solid-state structures were investigated using single crystal X-ray crystallography. The pyridazines were used as bidentate ligands in M(II)(bipy)2} and tris(homoleptic) complexes (M = Fe, Ru). The optical and electrochemical properties of these complexes reflect the electron accepting character of the new ligands. The facial and meridional isomers of the tris complexes could be separated by column chromatography
A dinuclear extension to constrained heteroleptic Cu(i) systems
作者:Belén Gil、Gareth A. Cooke、Deanne Nolan、Gearóid M. Ó Máille、Sunil Varughese、Longsheng Wang、Sylvia M. Draper
DOI:10.1039/c1dt10275c
日期:——
This article reports the synthesis and optical properties of three dinuclear, cationic copper complexes [Cu2(μ-dppm)2(μ-L)](NO3)2 (dppm diphenyldiphosphinomethane, L: LA 3,6-bis(2-pyridyl)-4,5-diphenyl-pyridazine, LB 3,6-bis(2-pyridyl)-4,5-di(4-pyridyl)-pyridazine and LC 3,6-bis(2-pyridyl)-8,9-diazafluoranthene). These were formed on the reaction of [Cu(μ-dppm)(NO3)]2 with a series of N-donor (bppn) ligands L. The single crystal X-ray structures of [Cu2(μ-dppm)2(μ-L)](NO3)2·CH2Cl2 were determined and revealed that in both, the two copper atoms are held by three bridging ligands, two dppm ligands and one bppn ligand acting as a tetradentate bridge. The absorption spectra of the complexes present a MLCT [Cu →π*(N∧N)] band in the λ 370–425 nm region. These new complexes exhibit red-orange MLCT-based emission in the solid-state with lifetimes in the microsecond range. In oxygen-free dichloromethane solution, the complex [Cu2(μ-dppm)2(μ-LC)]2+ has a long lifetime of 22.8 μs. The long emission lifetimes are attributed to a rigid conformation that precludes the possible distortion of the copper in the excited state.