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Oxidative halogenation with trityl chloride provides convenient access to Ce(IV) and U(IV) chloroamides [M(N{SiMe(3)}(2))(3)Cl] and their N-heterocyclic carbene derivatives, [M(L)(N{SiMe(3)}(2))(2)Cl] (L = OCMe(2)CH(2)(CNCH(2)CH(2)NDipp) Dipp = 2,6-iPr(2)C(6)H(3)). Computational analysis of the bonding in these and a fluoro analogue, [U(L)(N{SiMe(3)}(2))(2)F], provides new information on the covalency in this relative rare oxidation state for molecular cerium complexes. Computational studies reveal increased Mayer bond orders in the actinide carbene bond compared with the lanthanide carbene bond, and natural and atoms-in-molecules analyses suggest greater overall ionicity in the cerium complexes than in the uranium analogues.

for collection of some of the analytical data, and Sasol Technology UK (studentship for Z. R. T.), the UK EPSRC (fellowship for P. L. A.) and the University of Edinburgh for funding. Supporting information:[ † ] Electronic supplementary information (ESI) available: Experimental and crystallographic details (CCDC reference numbers 775504 and 775505) and spectroscopic data. For ESI and crystallographic data in CIF or other electronic format see http://dx. AbstractA simple coordination complex of uranium(III), a uranium tris(amide), can selectively couple gaseous CO to the linear ynediolate [OCCO] 2− dianion, at room temperature and pressure, regardless of the reagent stoichiometry. This product exhibits further reactivity upon warming in the form of the addition of a C-H bond of a methyl group across the C C triple bond, this second carbon-carbonbond forming reaction generating a functionalised enediolate dianion.

This tutorial review highlights the most promising methods for the preparation of well-defined copper metal and oxide nanocrystals. These methodologies could be applied to other metals. We present the main synthetic strategies and associated mechanisms to control monodispersity, size, morphology and structure of metal and oxide nanomaterials which can adopt spherical, polyhedral, cubic, rod, wire, plate shapes and possibly hollow structures. We also consider the scale-up of the production of these nanocrystals, which is crucial for a wide range of potential applications such as catalysis, photovoltaics, electronics, optics and electrocatalysis.

Selected PNP and SNS ethylene trimerization ligands have been coordinated to Cr II and Cr III , and further reactions of these complexes have been studied. The ligands are easily deprotonated to afford monoanionic tridentate ligands. All prepared complexes gave ethylene trimerization catalysis with varying degrees of activity upon activation with both MAO and AlR 3 /B(C 6 F 5 ) 3 . The results of this study show that the role of MAO during activation is one of deprotonation, Cr reduction, and cation generation. A Cr II f Cr IV cationic mechanism is suggested.