Synthesis, Structural Characterization, and Density Functional Study of Homo- and Heteropolyhalide Complexes of CuII with Dien and Dpta Ligands: Crystal Structure of [Bis(3-aminopropyl)amine](bromo)(diiodobromo)copper(II)

A Novel Family of Polyiodo-Bromoantimonate(III) Complexes: Cation-Driven Self-Assembly of Photoconductive Metal-Polyhalide Frameworks

In the presence of different cations, reactions of [SbBr₆ ]^3- and I₂ result in a new family of diverse supramolecular 1D polyiodide-bromoantimonate networks. The coordination number of Sb, as well as geometry of assembling {I_x }^n- polyhalide units, can vary, resulting in unprecedented structural types. The nature of I⋅⋅⋅Br interactions was studied by DFT calculations; estimated energy values are 1.6-6.9 kcal mol^-1 . Some of the compounds showed strong photoconductivity in thin films, suggesting multiple feasible applications in optoelectronics and solar energy conversion.

Dimerization of a mixed-carbene PdII dibromide complex by elemental iodine

A monomeric Pd^II complex bearing a mixed carbocyclic/N-heterocyclic carbene ligand and two bromides was reacted with an excess of elemental iodine, which resulted in the surprising removal of one bromide ligand and dimerization of the mixed-carbene complex to form di-μ-bromido-bis{[1-(cyclohepta-2,4,6-trien-2-yl-1-ylidene-κC¹)-3-(2,6-diisopropylphenyl)imidazol-2-ylidene]palladium(II)} bis(pentaiodide) dichloromethane monosolvate, [Pd₂Br₂(C₂₂H₂₄N₂)₂](I₅)₂·CH₂Cl₂. The dimeric complex features a slightly distorted square-planar core of two Pd^II centres bridged by two bromide ligands, which lie in the same plane as the seven- and five-membered rings of the bidentate carbene ligand. The counter-ions in the single crystal were found to be pentaiodide monoanions featuring their typical V-shape, whereas for the bulk material, a mixture of Br/I interhalides is proposed.

Comparison of halogen bonding networks with Ru(ii) complexes and analysis of the influence of the XB interactions on their reactivity

Coordination compounds of formula [Ru(Cl)₂(CNR)₄] are interesting building blocks for the preparation of halogen bonding supramolecular networks, since the chloride ligand is a good XB acceptor. When using I₂ as the XB donor, an unexpected reaction on the ruthenium coordination sphere happens where the chloride ligands are substituted by iodides. The isolation of several intermediates with different substitution degrees and showing XB interactions in a solid state network evidenced the clear influence of the XB species in this unusual reaction process. The extension of the studies to bromine gave the analogous result, i.e. the substitution of the chloride ligands by bromides. Furthermore, changing the organic substituent in the isocyanide ligands from alkyl to aryl does not affect the outcome of the reaction; however the process is faster when the alkyl substituents are present. In the course of the study of these reactions we have isolated a whole range of XB-based networks were interactions such as ClI-I, BrBr-Br, II-I and IBr-Br are present, a systematic comparison of the XB structural features for the different networks isolated and the influence in their reactivity has been performed.