Aurophilicity versus mercurophilicity: impact of d10-d10 metallophilic interactions on the structure of metal-rich supramolecular assemblies.

Treatment of U-shaped, binuclear Cu(I) complexes 1,1' (1, counterion: BF(4)(-); 1', counterion: PF(6)(-)) with metal cyanide linear linkers K[Au(CN)(2)] (3) and Hg(CN)(2) (4) lead to formation of new supramolecular assemblies 5,5' and 6,6', respectively, in good yield. These derivatives have been characterized by NMR spectroscopy, IR, and X-ray diffraction studies. Derivative 5,5' are supramolecular metallacycles in which intramolecular aurophilic interactions between the Au(I) metal centers of the linkers are observed. Derivative 5 crystallizes as a single solid phase, whereas derivative 5' is characterized in the solid state as four different pseudo-polymorphs (5'a-d). Notably in the case of phase 5'd, a dimer of supramolecular metallacycles bounded by intermolecular aurophilic interactions is formed. Conversely, derivatives 6,6' present large structural diversity depending on the nature of the counterion. Derivative 6 is a supramolecular rectangle in which the Hg(II)-Hg(II) metal distance suggests mercurophilic interaction, whereas 6' crystallizes as two different pseudo-polymorphs 6'a,b, that is, a one-dimensional coordination polymer and one oligomer with no short Hg(II)-Hg(II) metal contacts, respectively. In derivatives 6,6', short contacts between the Hg(II) metal centers and fluorine atoms of the counterions are also observed, which may explain the counterion structural dependence of these supramolecular assemblies based on Hg(II) metal cyanide linker. Comparison of the different solid-state structures characterized highlights the importance of weak secondary interactions between the linkers for the formation supramolecular metallacycles from molecular clips 1,1' and suggests the range of energies required for these interactions to form metallacycles and to induce self-aggregation.

The first example of a Pt...Pt interaction in platinum(ii) complexes bearing bulky tri-tert-butyl-2,2':6',2''-terpyridine pendants via conformational control of the calix[4]arene moiety.

An unprecedented short Pt...Pt contact between sterically bulky Pt((t)Bu(3)trpy) alkynyl moieties has been observed in the X-ray crystal structure of a dinuclear platinum(ii) complex bridged by a diethynylcalix[4]arene derivative; the complex in its crystalline state showed a red shift in the emission maxima at 298 K and 77 K relative to its powder form, which has been attributed to the presence of a metal-metal interaction in the crystal lattice.

Synthesis, structure and luminescence studies of heterometallic gold(I)-copper(I) and -silver(I) alkynyl clusters/aggregates.

A series of pentanuclear gold(I)-copper(I) and -silver(I) mixed-metal alkynyl complexes, [(n)Bu(4)N][Au(3)M(2)(C triple bond CC(6)H(4)R-p)(6)] [M = Cu, R = OMe, O(n)Bu, O(n)Hex, Me, Et; M = Ag, R = Et, O(n)Hex] have been synthesized. The complexes were found to be emissive both in the solid state and in fluid solutions. DFT calculations at the B3LYP level of theory were performed on [Au(3)M(2)(C triple bond CC(6)H(4)Me-p)(6)](-) (M = Cu, Ag) to provide an understanding on the electronic structure of the complexes.

Synthesis, characterisation, electrochemistry and luminescence studies of 9-anthrylgold(I) complexes.

Reaction of mono- and dinuclear gold(I) phosphine chloride precursors with an excess of organolithium reagent C14H9Li in dry diethyl ether or THF gave mononuclear [(PPh3)Au(C9H14)] and dinuclear [(P--P)Au2(C14H9)2] (P--P = dppm, dcpm) and [(dcpm)Au2Br(C14H9)], respectively. These complexes were found to be emissive both in the solid state and in fluid solutions.