Oligonuclear cyanide complexes from silver containing building blocks
摘要:
The complexes LnM-CN-Ag-CN with LnM=Cp(dppe)Fe or Cp(PPh3)(2)Ru are available from [Ag(CN)(2)](-) and [LnM](+) or LnM-CN. They are precursors of [LnM-CN-Ag-NC-MLn](+). Likewise the trinuclear complexes [LnM'-CN-Ag-NC-M'L-n](+) with LnM'=(TPA)Cu and cis-(bpy)(2)FeCN have been prepared. Irrespective of the CN attachment in the starting materials the cyanide-bridged compounds always contain M-CN-Ag arrays, i.e. silver-isocyanide coordination, thereby proving the lability of the silver-cyanide linkage. Electrochemical measurements have shown that there is no electronic communication between the outer metal centers in the trinuclear complexes. (C) 2000 Elsevier Science B.V. All rights reserved.
Two chiral dinuclear cyanide/isocyanide-bridged complexes (R)-[Cp(dppe)Fe–CN–Fe(dppp)Cp]PF6 (1[PF6]) and (R)-[Cp(dppe)Fe–NC–Fe(dppp)Cp]PF6 (2[PF6]), and their mono-oxidation products (R)-[Cp(dppe)FeII–CN–FeIII(dppp)Cp] [PF6]2 (1[PF6]2) and (R)-[Cp(dppe)FeIII–NC–FeII(dppp)Cp][PF6]2 (2[PF6]2) were synthesized and fully characterized. The electronic spectra of both the mixed-valence complexes 1[PF6]2 and 2[PF6]2 exhibit a strong and broad absorption band with two discernable peaks in the NIR region, which are attributed to Fe(II)–Fe(III) IVCT transitions. The attributions are supported by the DFT calculations. Under irradiation with a nanosecond laser at 1064 nm, the measured third-order NLO results of all four cyanide-bridged complexes showed that complexes 1+ and 2+ do not exhibit an NLO response, but their one-electron oxidation complexes 12+ and 22+ exhibit a strong NLO response due to a resonance enhanced effect. In addition, both complexes 12+ and 22+ display RSA and self-defocusing effects and show good optical limiting behavior in a broadband range.
Abstract In this report, two new binuclearmixed-valence (MV) compounds and their one-electron oxidation products, [MeCpLRu(μ-CN)Fe(dppe)Cp][PF6]n (L = dppe, (PPh3)2) (n = 1, 2), were synthesized and thoroughly characterized by single-crystal X-ray diffraction analysis. Complexes 12+ and 22+ are one-electron oxidation products of 11+ and 2+, respectively. The electronicabsorption results indicate that there
Synthesis, structural and metal-to-metal charge transfer properties of cyanide-bridged compound [Fe<sup>II/III</sup>-NC-Ru<sup>II</sup>-CN-Fe<sup>II/III</sup>]
作者:Yong Wang
DOI:10.1039/d1nj05900a
日期:——
one-electron oxidation product 2 is mainly attributed to RuII and FeII → FeIII MMCT transitions, and the MMCT of the two-electron oxidation product 3 is mainly attributed to RuII → FeIII MMCT transitions. The IR, EPR, Mössbauer spectroscopy and magnetic properties indicate electrondelocalization in complexes 2 and 3, and that of 3 is much stronger than that of 2. The two-electron oxidation product 3
氰化物桥接配合物反式-[Cp(dppe)Fe(NC)Ru II ( t bupy) 4 (CN)Fe(dppe)Cp][PF 6 ] n ( t bupy = 4-叔丁基吡啶, n = 2, 3 和 4 分别为1-3, ) 被系统地合成和表征为三种不同的氧化还原状态。单晶 X 射线衍射分析、IR、电化学、电子吸收光谱、EPR 和穆斯堡尔光谱清楚地揭示了配合物1-3的详细电子结构,这些发现使我们能够了解伴随氧化还原态变化的结构和电子态的系统变化。一电子氧化产物2的金属间电荷转移 (MMCT)主要归因于 Ru II和 Fe II → Fe III MMCT 跃迁,二电子氧化产物3的 MMCT主要归因于 Ru II → Fe III MMCT 跃迁。IR、EPR、穆斯堡尔光谱和磁性表明配合物2和3中的电子离域,并且3比2强得多. 就EPR、穆斯堡尔光谱和磁性而言,双电子氧化产物3可以在低温下定位,但在室温下离域。
Long Range Metal‐Metal Interactions Along Fe−NC−Ru−CN−Fe Chains
作者:Tianlu Sheng、Heinrich Vahrenkamp
DOI:10.1002/ejic.200300656
日期:2004.3
Trinuclear complexes with linear FeII−NC−RuII−CN−FeII arrays were obtained by attachment of FeCp(dppe) units to the cyanoruthenium complexes trans-[Ru(CN)2(Py)4] (Py = pyridine, 4-methylpyridine, 4-ethylpyridine) . From their cyclic voltammograms it can be concluded that there are long-range metal−metal interactions between their external iron centers. Partial oxidation led to the isolation of the corresponding
Influence of the central diamagnetic cyanidometal on the distant magnetic interaction in cyanide-bridged Fe(<scp>iii</scp>)–M(<scp>ii</scp>)–Fe(<scp>iii</scp>) complexes
This work shows that for the investigated FeIII–NC–MII–CN–FeIII complexes the magnetic coupling strength between the distant FeIII ions increases with the diamagnetic cyanidometal bridge in the order of Fe < Ru < Os.