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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 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 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.

A model for the corpus site of monocopper enzyme that provides not only a biomimetic N3 neutral coordination site but also a cavity that controls the access to the metal center is described. These supramolecular systems provide a rare and interesting model for the hydrophobic substrate channel giving access to a metalloenzyme active site.

Research is presented concerning the properties of a supramolecular system which has the capacity to act as a biomimetic receptor for neutral guests. This ligand was investigated using 1H nuclear magnetic resonance spectroscopy.

The uptake of fructose and mannose in the opportunistic pathogen Aeromonas hydrophila is investigated. A. hydrophila has a fructose-specific and a mannose-specific transport system via separate phosphotransferase systems (PTS). Both fructose PTS and mannose PTS in A. hydrophila exhibit cross reactivities with other PTS from various organisms. The metabolic pathway undergone by these substrates upon entering the cell are discussed.

The design of new materials with tunable properties and intrinsic recyclability, derived from biomass under mild conditions, stands as a gold standard in polymer chemistry. Reported herein are platinum complexes which catalyze the formation of poly(silylether)s (PSEs) at low catalyst loadings. These polymers are directly obtained from dual‐functional biobased building blocks such as 5‐hydroxymethylfurfural (HMF) or vanillin, coupled with various dihydrosilanes. Access to different types of copolymer architectures (statistical or alternating) is highlighted by several synthetic strategies. The materials obtained were then characterized as low Tg materials (ranging from −60 to 29 °C), stable upon heating (T−5% up to 301 °C) and resistant towards uncatalyzed methanolysis. Additionally, quantitative chemical recycling of several PSEs could be triggered by acid‐catalyzed hydrolysis or methanolysis. These results emphasize the interest of biobased poly(silylether)s as sustainable materials with high recycling potential. [ABSTRACT FROM AUTHOR]

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.

The coordination chemistry of Zn in an N3ArOH environment is explored and the calix[6]N3ArOH-based complexes are shown to act as an acid-base switch for guest binding. The ligands are based on calix[6]arenes that present two imidazole arms and an amino phenol moiety at the narrow rim.

The host-guest properties of calix[6]tren 1 are evaluated. The receptor is based on a calix[6]arene that is covalently capped at the narrow rim by a tren unit and the system presents a concave hydrophobic cavity with, at its bottom, a grid-like nitrogenous core.

Oxo alcoxo metallic clusters can be employed as inorganic nanobuilding blocks to obtain well-defined organic-inorganic hybrid materials. It is found that a better understanding of the surface reactivity of these clusters should allow optimization of the elaboration of hybrid materials through a better control of the hybrid interface.

An experiment which was conducted to produce 11alpha- and 11beta- modified androst-5-ene derivatives as well as the exo- and endocyclic dehydrated compounds, using the oxalate derivatives of the highly hindered 11beta-hydroxyandrost-5-enes is presented.

The complexation of vanadium (V) by five dipeptides differing by the nature of the side chains is studied using spectroscopic methods. The result shows that peptides or proteins cannot interact with vanadium by random binding at any peptide linkages as terminal amino and terminal carboxylate may be both required for a vanadium complexation.

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.

2D Ruddlesden‐Popper (RP) and Dion‐Jacobson (DJ) halide perovskite structures are characterized by the n parameter that represents the number of PbI6 layers in the spacer‐separated perovskite slabs. In most of the literature, n is referred to the initial composition of the precursor solution and, then, to the initial spacer content. In this approach, the fact that the spacer can be partially lost upon annealing is not considered. Here, the chemical processes occurring upon the preparation of reduced‐dimensional halide perovskite thin films of both families are investigated with a special focus on the organic cations composition and, especially, the evolution of n values. For each family, several spacers are investigated. It is shown that a large amount of monoammonium spacer cations is progressively eliminated upon annealing for the 2D‐RP perovskites, while, on the contrary, the final composition is close to the initial one in the case of the diammonium spacer cations of the 2D‐DJ perovskites. The elimination is related to the volatilization of the species after their deprotonation and the phenomenon can be regulated by halide additives. This work provides an important insight into the chemistry of the 2D perovskite layers and shows the importance of determining their “true” n value. [ABSTRACT FROM AUTHOR]

Research demonstrating the stability of the complex Zn-aqua is presented. Particular attention is given to to clarifications of the X-ray structural analysis of the compound and to ways in which it can be used for active zites of enzymes based on mono-zinc.