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A family of luminescent pyrenyl‐(NHC)‐M−Cl coinage metal complexes has been prepared and fully characterized (NHC=N‐heterocyclic carbene). Two classes of complexes are described: (M=Cu (1 a), Ag (2 a), Au (3 a) where pyrenyl‐(NHC)=1‐pyrenyl‐3‐methyl‐Imidazolin‐2‐ylidene and M=Cu (1 b), Ag (2 b), Au (3 b) with pyrenyl‐(NHC)=1‐pyrenyl‐3‐naphthyl‐Imidazolin‐2‐ylidene. The molecular structures of the six complexes were confirmed by single crystal X‐ray diffraction studies. All complexes were found to be emissive both in solution and solid state. The use of the chromophoric‐(NHC) ligand endows to these complexes emissive properties in solution in the blue region (376–397 nm). The presence of the naphthyl‐substituent in the 1 b–3 b series enhances the quantum yields relative to the methyl‐series 1 a–3 a. In particular, the carbene gold complexes were the most emissive and displayed the highest quantum yields. [ABSTRACT FROM AUTHOR]

The employment of N-heterocyclic carbenes (NHCs) to design luminescent metal compounds has been the focus of recent intense investigations because of the strong σ-donor properties, which bring stability to the whole system and tend to push the d–d dark states so high in energy that they are rendered thermally inaccessible, thereby generating highly emissive complexes for useful applications such as organic light-emitting diodes (OLEDs), or featuring chiroptical properties, a field that is still in its infancy. Among the NHC complexes, those containing organic chromophores such as naphthalimide, pyrene, and carbazole exhibit rich emission behavior and thus have attracted extensive interest in the past five years, especially carbene coinage metal complexes with carbazolate ligands. In this review, the design strategies of NHC-based luminescent platinum and iridium complexes with large spin–orbit-coupling (SOC) are described first. Subsequent paragraphs illustrate the recent advances of luminescent coinage metal complexes with nucleophilic- and electrophilic-based carbenes based on silver, gold, and copper metal complexes that have the ability to display rich excited state emissions in particular via thermally activated delayed fluorescence (TADF). The luminescence mechanism and excited state dynamics are also described. We then summarize the advance of NHC–metal complexes in the aforementioned fields in recent years. Finally, we propose the development trend of this fast-growing field of luminescent NHC–metal complexes. [ABSTRACT FROM AUTHOR]

The racemic traingular supramolecular host {Cp(super *)Rh(5-chloro-2,3-dioxopyridine)}3] was prepared in high yield. Treatment with LiCl followed by addition of silver salt AgOTf gave the triflate salt species [Lisubset{Cp(super *)Rh(5-chloro-2,3-dioxopyridine)}3][OTf].

The article titled "A Novel Family of Luminescent Pyrenyl-(N-Heterocyclic Carbene)-Halogenated Coinage Metal Complexes: Synthesis, Crystal Structures, and Optical Properties" discusses the synthesis and characterization of a new family of stable pyrenyl-(NHC)MCl coinage metal complexes. These complexes, which include copper, silver, and gold, were obtained in high yields and their molecular structures were determined through X-ray diffraction studies. The complexes exhibit emissive properties in the blue region, similar to the natural blue light produced by phytoplankton on the ocean's surface at nightfall. The article provides further details on this research. [Extracted from the article]

Research has been conducted on the quinone methides and phenol tautomers. The reactivity of the iridium and rhodium o-quinone methide complexes and phenol ortho functionalization mediated by iridium are discussed.

Research has been conducted on tris(solvent)rhodium and -ridium complexes. The X-ray molecular structures of these complexes have been investigated and the results indicate that the structures are of piano-stool type.

An ABMX spin system study can be used to take graduate students of chemistry from experimental to calculated spectra. The experimental (super.1)H NMR spectrum of the cation (Co(sub.2)(CO)(sub.5))(mu-HC-triple bond-CCH(sub.2)-P(Phi(sub.2))-CH(sub.2)-P(Phi(sub.2))))(super.+), a phosphonium complex, which has both ABX and ABMX subspectra, is given.

New bonding modes, fluxional behavior, and reactivity in dinuclear transition metal complexes bridged by four-electron donor unsaturated hydrocarbons are discussed. The type of coordination in dinuclear systems varies while moving from one system to the other. The similarity in the dynamic behavior of these complexes are due to the migration of the bridging hydrocarbyl ligand from one atom to the other, rotation about the C-C bond, and the internal rearrangement of the dinuclear cluster. The synthesis and reactions involving the dinuclear propargyl radicals attached to fulvalne ligands are given.

A combination of X-ray diffraction, NMR and IR spectroscopy, and DFT calculations are used to study the hydrogen bonding phenomena for the series of complexes of the form Cp*Ir([L.sub.1])([L.sub.2])(phosphine). The obtained results highlighted the difficulty of characterizing hemilabile, bifunctional complexes and the importance of innocent ligand substituents in determining structure and dynamics.

Luminescent cyclometalated rhodium(III) and iridium(III) complexes are prepared and characterized. The comparison of the photophysical behavior of the rhodium(III), iridium(III) and ruthenium(II) complexes has disclosed the impact of the carboxylic groups that has affected the intraligand charge-transfer (ILCT), metal-to-ligand charge-transfer/ligand centered (MLCT)/LC states in different ways.

The synthesis of a new family of ruthenium complexes of general formula [Ru[(DIP).sub.2][L.sub.2]][sup.2+], where DIP=4,7-diphenyl-1,10-phenanthroline, a bidentate ligand with extended aromatic system, is reported. Complex [Ru[(DIP).sub.2][MeOH].sub.2]][[OTf].sub.2] displayed a trans configuration of the DIP ligands.

A study is conducted on the binding of DNA with optically pure ruthenium bipyridyl complexes incorporating carboxylic functions. The preliminary results indicate that the carboxylic functions play an important role in the binding process.

Research has been conducted on supramolecular architecturs. The authors report that these architectures have been constructed via self-assembly and obtained via the use of AgCF (sub)3 SO (sub)3 (super)- as a building block.