Synthesis, structure, spectroscopy and redox energetics of a series of uranium(IV) mixed-ligand metallocene complexes
Synthesis, structure, spectroscopy and redox energetics of a series of uranium(IV) mixed-ligand metallocene complexes
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DOI：
10.1016/j.crci.2010.04.008
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发表时间：
2010-06
影响因子：
1.6
通讯作者：
Robert K. Thomson;B. Scott;D. E. Morris;J. Kiplinger
中科院分区：
文献类型：
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作者：
Robert K. Thomson;B. Scott;D. E. Morris;J. Kiplinger
一系列的铀(IV) mixed-ligand amide-halide / pseudohalide复合物(C 5我5)2 U (N(森那美3)2)(X) (X = F (1), Cl (2), Br (3), (4), N 3(5),以区域(6)),(C 5我5)2 U(一组2)(X) (X = Cl (7), N 3(8)),和(C 5我5)2 U [N (Ph)(森那美3)](X) (X = Cl (9), N 3(10))已经由一个电子氧化相应的铀(III)酰胺前体使用铜卤化物、银异氰酸酯,或叠氮化三苯基膦黄金(I)。这些配合物在固态和溶液中均观察到agstic U⋯H-C相互作用和η 3-（N， C, C '）配位。c5me5配体质子在1h核磁共振光谱中的化学位移值与（c5me5） 2 U [N (sime3) 2](X)配合物的U IV/U III还原电位呈线性相关，表明它们有一个共同的来源，即辅助(X)配体对金属的总体σ-/π给予，有助于这两个观测结果的产生。1-6系列配合物的光谱由（c5me5） 2u [N (sime3) 2]核心主导，由于卤化物/伪卤化物的身份而产生了微小的变化。氟配合物（c5me5） 2u [N (sime3) 2](F)(1)的电化学和紫外可见-近红外光谱行为反映了氟配体可观的供π能力。本文还报道了新的三价铀酰胺配合物（c5me5） 2u [N (Ph)(sime3)]（THF）和两种新的弱配电解质[Pr 4n][B {3,5 -(CF 3) 2c6h3} 4]和[Pr 4n][B (c6f5) 4]的合成。
A series of uranium (IV) mixed-ligand amide–halide/pseudohalide complexes (C 5 Me 5) 2 U [N (SiMe 3) 2](X)(X= F (1), Cl (2), Br (3), I (4), N 3 (5), NCO (6)),(C 5 Me 5) 2 U (NPh 2)(X)(X= Cl (7), N 3 (8)), and (C 5 Me 5) 2 U [N (Ph)(SiMe 3)](X)(X= Cl (9), N 3 (10)) have been prepared by one electron oxidation of the corresponding uranium (III) amide precursors using either copper halides, silver isocyanate, or triphenylphosphine gold (I) azide. Agostic U⋯ H–C interactions and η 3-(N, C, C′) coordination are observed for these complexes in both the solid-state and solution. There is a linear correlation between the chemical shift values of the C 5 Me 5 ligand protons in the 1 H NMR spectra and the U IV/U III reduction potentials of the (C 5 Me 5) 2 U [N (SiMe 3) 2](X) complexes, suggesting that there is a common origin, that is overall σ-/π-donation from the ancillary (X) ligand to the metal, contributing to both observables. Optical spectroscopy of the series of complexes 1–6 is dominated by the (C 5 Me 5) 2 U [N (SiMe 3) 2] core, with small variations derived from the identity of the halide/pseudohalide. The considerable π-donating ability of the fluoride ligand is reflected in both the electrochemistry and UV-visible-NIR spectroscopic behavior of the fluoride complex (C 5 Me 5) 2 U [N (SiMe 3) 2](F)(1). The syntheses of the new trivalent uranium amide complex,(C 5 Me 5) 2 U [N (Ph)(SiMe 3)](THF), and the two new weakly-coordinating electrolytes,[Pr 4 N][B {3, 5-(CF 3) 2 C 6 H 3} 4] and [Pr 4 N][B (C 6 F 5) 4], are also reported.