The exploitation of molecular catalysts for CO 2 electrolysis requires their immobilization on the cathode of the electrolyzer. As an illustration of this approach, a Ni-cyclam complex with a cyclam derivative functionalized with a pyrene moiety is synthesized, found to be a selective catalyst for CO 2 electroreduction to CO, and immobilized on a carbon nanotubecoated gas diffusion electrode by using a noncovalent binding strategy. The as-prepared electrode is efficient, selective, and robust for electrocatalytic reduction of CO 2 to CO. Very high turnover numbers (ca. 61460) and turnover frequencies (ca. 4.27 s À 1) are enabled by the novel electrode material in organic solvent-water mixtures saturated with CO 2. This material provides an interesting platform for further improvement.

A library of eleven cationic gold(III) complexes of the general formula [(C C)Au(N N)] + when C C is either biphenyl or 4,4'-ditertbutyldiphenyl and N N is a bipyridine, phenanthroline or dipyridylamine derivative have been synthesized and characterized. Contrasting effects on the viability of the triple negative breast cancer cells MDA-MB-231 was observed from a preliminary screening. The antiproliferative activity of the seven most active complexes were further assayed on a larger panel of human cancer cells as well as on non-cancerous cells for comparison. Two complexes stood out for being either highly active or highly selective. Eventually, reactivity studies with biologically meaningful amino acids, glutathione, higher order DNA structures and thioredoxin reductase (TrxR) revealed a markedly different behavior from that of the well-known coordinatively isomeric [(C N C)Au(NHC)] + structure. This makes the [(C C) Au(N N)] + complexes a new class of organogold compounds with an original mode of action.

A series of ten cationic complexes of the general formula [(C^C)Au(P^P)]X, where C^C = 4,4′-di-tert-butyl-1,1′-biphenyl, P^P is a diphosphine ligand, and X is a noncoordinating counteranion, have been synthesized and fully characterized by means of chemical and X-ray structural methods. All the complexes display a remarkable switch-on of the emission properties when going from a fluid solution to a solid state. In the latter, long-lived emission with lifetime τ = 1.8–83.0 μs and maximum in the green-yellow region is achieved with moderate to high photoluminescence quantum yield (PLQY). This emission is ascribed to an excited state with a mainly triplet ligand-centered (3LC) nature. This effect strongly indicates that rigidification of the environment helps to suppress nonradiative decay, which is mainly attributed to the large molecular distortion in the excited state, as supported by density functional theory (DFT) and time-dependent DFT (TD-DFT) computation. In addition, quenching intermolecular interactions of the emitter are avoided thanks to the steric hindrance of the substituents. Emissive properties are therefore restored efficiently. The influence of both diphosphine and anion has been investigated and rationalized as well. Using two complexes as examples and owing to their enhanced optical properties in the solid state, the first proof-of-concept of the use of gold(III) complexes as electroactive materials for the fabrication of light-emitting electrochemical cell (LEC) devices is herein demonstrated. The LECs achieve peak external quantum efficiency, current efficiency, and power efficiency up to ca. 1%, 2.6 cd A–1, and 1.1 lm W–1 for complex 1PF6 and 0.9%, 2.5 cd A–1, and 0.7 lm W–1 for complex 3, showing the potential use of these novel emitters as electroactive compounds in LEC devices.

The two independent O _ N _ Oa nd N _ Nc oordination sites of an ewly synthesized bis[2-(hydroxyphenyl)-1,2,4-triazole] platform have been exploited to prepare fourm onometallic neutral (O _ N _ O)Pt II complexes carryingD MSO, pyridine, triphenylphosphine, or N-heterocyclic carbene as the fourth ligand.T hen, the second N _ Nc oordination site was used to introduce an IR-active rhenium tricarbonyl entity,a ffording the four correspondingh eterobimetallic neutral Pt II / Re I complexes,a sw ell as ac ationic Pt II /Re I derivative.X-ray crystallographic studiess howed that distortiono ft he organic platform occurred to accommodate the coordination geometry of both metal centers. No ligand exchange or transchelation occurred upon incubation of the Pt II complexes in aqueouse nvironment or in the presence of Fe III ,r espectively. The antiproliferativea ctivity of the ligand and complexes was first screened on the triple-negative breast cancerc ell line MDA-MB-231. Then, the IC 50 values of the most active candidates were determined on aw ider panel of human cancerc ells (MDA-MB-231, MCF-7, and A2780), as well as on anontumorigenic cell line (MCF-10A). Low micromolar activities were reached for the complexes carrying aD MSO ligand, making them the first examples of highly active, but hydrolytically stable, Pt II complexes. Finally,t he characteristic mid-IRs ignature of the {Re(CO) 3 }f ragment in the Pt/Re heterobimetallic complexes wasu sed to quantify their uptake in breast cancer cells.

This paper reports the design, synthesis and cytotoxicity studies of two new isoxazole‐derived aroylhydrazone ligands and their dinuclear copper(II) complexes. Compounds were fully characterized by various spectroscopic and analytical techniques. The molecular structures of four derivatives were confirmed by X‐ray crystallography. The stability of the ligands and the complexes in aqueous medium was monitored spectroscopically. Both the ligands and the complexes were shown to interact with calf thymus DNA (ct‐DNA). Additionally, structures containing a phenol pendant arm were significantly more cytotoxic than those carrying a pendant pyridine substituent, reaching sub‐micromolar IC50 values on the triple‐negative human breast cancer cell line MDA‐MB‐231. The metal chelation and transchelation ability of the compounds towards FeII, FeIII and ZnII ions was explored as a possible mechanism of action of these compounds.