Iridium

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Iridium corroles

This work reports the synthesis and full characterization of 5,10,15-tris-pentafluorophenylcorrolato-iridium(III) bis-trimethylamine 1 and its octabromo derivative 2. The corrole is planar in both cases (the mean deviation from the plane is as low as 0.0371 A for 1 and 0.0325 A for 2), the UV-vis spectra display a split Soret band with a shoulder attributable to an MLCT transition, and cyclic voltammetry reveals that the iridium(II) oxidation state cannot be accessed, while the oxidation to formal iridium(IV) complexes is achieved at much lower potentials than in other coordination environments.     

Rhodium und Iridium

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A Cornucopia of Iridium Nitrogen Compounds Produced from Laser-Ablated Iridium Atoms and Dinitrogen

The reaction of laser-ablated iridium atoms with dinitrogen molecules and nitrogen atoms yield several neutral and ionic iridium dinitrogen complexes such as Ir(N₂), Ir(N₂)⁺, Ir(N₂)₂, Ir(N₂)₂⁻, IrNNIr, as well as the nitrido complexes IrN, Ir(N)₂ and IrIrN. These reaction products were deposited in solid neon, argon and nitrogen matrices and characterized by their infrared spectra. Assignments of vibrational bands are supported by ab initio and first principle calculations as well as ^14/15N isotope substitution experiments. The structural and electronic properties of the new dinitrogen and nitrido iridium complexes are discussed. While the formation of the elusive dinitrido complex Ir(N)₂ was observed in a subsequent reaction of IrN with N atoms within the cryogenic solid matrices, the threefold coordinated iridium trinitride Ir(N)₃ could not be observed so far.     

Iridium Catalyzed Carbocyclizations: Efficient (5+2) Cycloadditions of Vinylcyclopropanes and Alkynes

Third‐row transition metal catalysts remain a largely untapped resource in cycloaddition reactions for the formation of medium‐sized rings. Herein, we report the first examples of iridium‐catalyzed inter‐ and intramolecular vinylcyclopropane (VCP)–alkyne (5+2) cycloadditions. DFT modeling suggests that catalysis by iridium(I) proceeds through a mechanism similar to that previously reported for rhodium(I)‐catalyzed VCP–alkyne cycloadditions, but a smaller free energy span for iridium enables substantially faster catalysis under favorable conditions. The system is characterized by up to quantitative yields and is amenable to an array of disubstituted alkynes and vinylcyclopropanes.     

Rhodium and Iridium Pyrazolato Blues

The staggered arrangement of the two dimers in 1 facilitates the formation of an almost linear chain of four metal centers that is held together by a nonsupported metal–metal bond. The intense color of the compounds and the fractional oxidation states of the metal atoms can be explained by electron delocalization along the chain. M=Rh, Ir.     

Trennung des Platins vom Iridium

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光敏化铱配合物三线态材料

铱配合物由于高的激发单线态到三线态的量子转化效率和可调节的三线态寿命,近年来在三线态光敏化应用领域备受瞩目.科学家们就调控铱配合物发光波长和发光量子效率已建立起有效的分子设计策略和原则,但对如何调控铱配合物的可见光吸光响应,三线态量子产率和寿命等光敏化应用要求的重要光物理参数的相关探索并不多,相应的分子设计策略和原则远未建立.本文介绍了铱配合物与光敏化过程相关的光物理特征,改进铱配合物可见光吸收性能、调控三线态量子产率和寿命的分子设计策略,综述了铱配合物近年来应用于染料敏化太阳能电池、三线态-三线态湮灭能量上转化和光裂解水制氢的研究进展,梳理了铱配合物分子结构与光敏化性能之间的部分关联关系.     

新试剂3，5-二溴吡啶偶氮-5-甲氧基酚与铱的三元配合物光度分析及结构研究

研究了新试剂３,５－二溴比啶偶氮－５－甲氧基酚与铱的显色反应。在水杨酸的存在下,于ＰＨ６．５的醋酸－醋酸盐缓冲溶液中,形成了配位比为Ｉｒ：ＤＢＰＭＰ：Ｒ＝１：１：１的橙红色的三元配合物。λｍａｘ＝５８８ｎｍ表观摩尔吸光系数ε＝１．９６＊１０＾５Ｌ／ｍｏｌ．ｃｍ。     

Mikromengen Rhodium und viel Iridium

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Spectrophotometric Determination of Iridium (IV) with 3-Nitroso-4-Hydroxy-5, 6-Benzocoumarin

Iridium(IV) gives a deep red complex with 3-nitroso-4-hydroxy-5,6-benzo-coumarin when heated on a boiling water-bath for about 10 minutes. The complex is soluble in 50% aqueous acetone medium and exhibits maximum absorption at 520nm. Beer's law is obeyed up to 10.5 ppm of iridium at 520 nm. Molar absorptivity is 1.28×10⁴ litre mole^-1 cm^-t and the sensitivity of the colour reaction is 0.015 μg Ir(IV)/cm². The composition of the complex is 1:3 as determined by Job's and logarithmic methods. Common anions and cations do not interfere in the determination.