f-Element-metal bond chemistry

Abstract

Compared to the overwhelming prevalence of f-elementcarbon, -nitrogen, -oxygen or -halide ligand linkages, the use of metal-based fragments as ligands is underdeveloped. This contrasts directly to the extensively developed fi elds of d-and p-block metal-metal complexes, which are still burgeoning. This review outlines the development of compounds that possess polarised covalent f-element-metal bonds. For this review, the f-element is defi ned as (i) a group 3 metal; (ii) a lanthanide metal; (iii) the actinide metals thorium or uranium. The metal is defi ned as: (i) a d-block transition metal; (ii) a group 13 metal (aluminium or gallium); (iii) a group 14 metal (silicon, germanium or tin); (iv) a group 15 metal (antimony or bismuth) metal. Although silicon, germanium and antimony are traditionally classifi ed as metalloids, they are included for completeness. We focus on complexes that have been structurally authenticated by single crystal X-ray diffraction, and we highlight novel aspects of their syntheses, properties and reactivities.

A Very Short Uranium(IV)–Rhodium(I) Bond with Net Double‐Dative Bonding Character

“…The majority of uranium–metal complexes contain a polarised covalent σ‐bond, which may be augmented by a weak π‐bonding interaction . However, examples with dative metal donors are few, since they lack a substantial electrostatic attractive force to pair the two metal ions.…”

Rare‐Earth Metal Oxo/Hydroxo Clusters – Synthesis, Structures, and Applications

“…[122] By using this peptoid as a supporting ligand, we achieved the preparation of pentadecanuclear lanthanide hydroxy clusters of the formula [Ln 15 (μ 3 -OH) 20 (PepCO 2 ) 10 (Ph 2 acac) 10 Cl]Cl 4 {Ln = Y, Eu, Tb, Dy; PepCO 2 = 2-[(3-{[(tert-butoxycarbonyl)-amino]methyl}benzyl)amino]} with both the dibenzoylmethanide and the CPPo monomer in its outer coordination sphere (Scheme 8 and Figure 9). [115,116] Scheme 8.…”

“…On the other hand, metal-tometal bonds between the lanthanides and main-group or transition metals have been intensively investigated in the last ten years. [15][16][17] Moreover, in rare-earth chemistry the metal cations favor high coordination numbers (8-12 most common) and have no strict preferences in coordination geometry. [3] To stabilize a cluster core consisting of rare-earth metal cations the presence of Lewis-basic ligands is beneficial but not needed in all cases.…”

“…[41] The use of tyrosine as an ancillary ligand prevents complete hydrolysis, a process that would otherwise lead to the formation of intractable metal hydroxides and/or oxides. As a result, Zheng et al reported the isolation of a finite-sized pentadecanuclear cluster core surrounded by 10 tyrosine ligands -[Eu 15 (Cl)(μ 3 -L-Tyr) 10 (μ 3 -OH) 20 (LTyrH = L-tyrosine). [41] Zheng et al and others also demonstrated that the use of an ancillary ligand is mandatory, because preventing the cluster core from undergoing further hydrolysis is the most important step in the controlled hydrolysis approach.…”

Die Renaissance der nichtwässrigen Uranchemie

“…Nach Berichten über zwei Beispiele von Uran(II)‐Komplexen (und sogar von Thorium(II)‐Komplexen),217 kann man spekulieren, dass auch molekulare Uran(I)‐ und Uran(0)‐Komplexe isolierbar sind. Uran‐Metall‐Bindungen wurden in diesem Aufsatz nicht betrachtet,26e,h, 29a,e und nur wenige Beispiele wurden beschrieben 218. Uran‐Uran‐Bindungen sind unter “normalen” Bedingungen unbekannt, wären aber in Anbetracht der vielen Metall‐Metall‐Bindungen zwischen Elementen der Gruppe 6 von großem Interesse 219.…”