Dark-Field Oxidative Addition-Based Chemosensing: New Bis-cyclometalated Pt(II) Complexes and Phosphorescent Detection of Cyanogen Halides
作者:Samuel W. Thomas、Koushik Venkatesan、Peter Müller、Timothy M. Swager
DOI:10.1021/ja065645z
日期:2006.12.1
halides) by either thermal or photochemical activation. We have applied this general reaction scheme to the development of a phosphorescence-based sensing system for cyanogen halides. To carry out structure-property relationship studies, a series of previously unreported Pt(II) complexes was prepared. Most of the complexes (excluding those that incorporated substituents on the ligands that forced steric
iodide or chloride salt gives the corresponding iodido- or chlorido(aryl) complexes. The fluorido(aryl) derivatives can be obtained from the iodido complexes by halide exchange using AgF. The chlorido- and fluorido(aryl) complexes display intense phosphorescence in deaerated CH2Cl2 solution and poly(methyl methacrylate) (PMMA) films at 298 K from triplet excited states primarily localized on the cyclometalated
phosphorecent Pt(IV) complexes is reported, which combine two cyclometalated 2-arylpyridine ligands and a dimetalated biaryl. The introduction of biaryl ligands is achieved under mild conditions through the oxidative addition of dibenzoiodolium ions to Pt(II) precursors to give Pt(IV) intermediates with a singly metalated 2-(2-iodoaryl)aryl ligand, followed by the reductive metalation of the C–I bond
报道了第一系列中性、三螯合、磷光 Pt( IV ) 配合物,它结合了两个环金属化 2-芳基吡啶配体和一个二金属化联芳基。联芳基配体的引入是在温和条件下通过将二苯并碘鎓离子氧化加成到 Pt( II ) 前体得到具有单金属化 2-(2-碘芳基)芳基配体的Pt( IV ) 中间体,然后还原金属化C-I 键。证明了通过衍生两种类型的配体来调节发射特性。
Photochemically Induced Cyclometalations at Simple Platinum(II) Precursors
Photochemical cycloplatinations of 2-arylpyridines and related C∧N ligands, as well as terdentate heteroaromatic N∧N∧C, N∧C∧N, and N∧C∧C compounds, are demonstrated using (Bu4N)2[Pt2Cl6] or [PtCl2(NCPh)2] as precursors at room temperature. Mono- or bis-cyclometalated Pt(II) complexes with C∧N ligands are obtained depending on excitation wavelength and precursor. Monitoring experiments show that photoexcitation