European Journal of Inorganic Chemistry最新文献

In this research, we introduce new members to the [Fe(^bzL)(NCE)₂] complex series by incorporating NCS⁻ and NCBH₃⁻ as co-ligands, expanding on our established tetradentate ^bzL ligand. The synthesis of three isostructural structures has allowed for a systematic tuning of SCO temperatures, with T_1/2 values ranging from 85 K for the S-α complex, featuring approximately 15 K thermal hysteresis, to 194 K for the Se-α complex, and a stable low-spin state up to 300 K for the B-α complex. This work demonstrates the efficacy of modulating SCO properties through variation of the NCE⁻ ancillary ligands. Furthermore, we conducted a comparative analysis of 21 analogs within this family. This analysis aims to elucidate the similarities and differences among the complexes and their correlation with SCO properties, furthering our understanding of the structural determinants that influence SCO behavior.

The Front Cover shows a gull on a beautiful sunset flying with a series of smaller cartoonish gulls. In between these gulls, the ingredients for a novel reductive transmetalation route are provided: “AlCp*” and ZnR₂ (R=aryl), which selectively react to yield compounds of the generic formula [AlCp*R₂]. As an example, a crystal structure is shown that spreads its newly introduced aryl rings as wings to fly with the big gull. Corroborated by quantum chemical calculations, such compounds found application for selective CO₂ insertion in their AlCp* moieties to yield small inorganic rings. More information can be found in the Research Article by E. Hevia and F. M. Dankert.

The exceptional reactivity observed in non-heme iron enzymes can be attributed to their capability to access high-valent iron oxygen species in their active site. Numerous inorganic model complexes have been reported to date, providing insights into the intricate structural and spectroscopic features of many iron-containing enzymes and advancing our understanding of their enzymatic reaction pathways. While the reactivities of synthetic iron complexes have been evaluated using various oxidants, the investigation into the formation of reactive intermediates has primarily focused on acetonitrile. However, water, which serves as the medium in biological systems, has been less frequently employed in these studies. Motivated by this, we conducted a comprehensive study on the generation of key reactive species using various oxidants with a model complex, [(BnTPEN)Fe(II)(OTf)]⁺ (1) (where BnTPEN=N-benzyl-N,N,N-tris(2-pyridylmethyl)-1,2-diaminoethane) in water, which yielded important findings. In water, a quantitative yield of Fe(IV)=O species was achieved with the oxidant NaIO₄. Additionally, we observed an equilibrium between side-on Fe(III)−OO and Fe(III)−OOH, with the latter eventually converting to Fe(IV)=O. The insights gained from this study are likely to be relevant in the chemistry of other Fe(II) complexes with polypyridyl pentadentate ligands.

A tridentate trimethylstannyl substituted alkyne based on the tribenzotriquinacene (TBTQ) scaffold has been transformed into several gold(I)phosphane complexes by tin-gold exchange. While the molecular structures of the gold(I) derivatives with less bulky trimethyl and dimethylphenylphosphane ligands exhibit intermolecular aurophilic interactions, the sterically demanding triphenylphosphane ligands inhibit the occurrence of Au⋅⋅⋅Au contacts. In addition, a hexanuclear gold(I) system was synthesised by terminal functionalisation of the hexaalkynyl TBTQ. Investigations of the photophysical properties of the gold(I)phosphane TBTQ compounds revealed their luminescent character at room temperature.

The Cover Feature illustrates the integration of a 3D porous polymer and its interaction with Congo Red molecules, highlighting the polymer′s efficient dye adsorption. The large cube represents a polymer network, with red and blue bonds indicating molecular bonds between different monomers. Floating chemical structures depict Congo Red dissolved in an aqueous solution with its adsorption into the material leading to a clearer background. More information can be found in the Research Article by N. Yang, R. Kunthom and H. Liu.

In this work, the A₂B₂-type Zn-porphyrin (ZnPorI₂) featuring vinyl and imidazolium groups was utilized to prepare porous organic polymers (POPs). The vinyl group served as the linking unit for copolymerization with rigid divinylbenzene (DVB). The imidazolium group introduced iodide ions (I⁻) into ZnPorI₂/nDVB (n=30, 50) as Lewis base. By fine-tuning the ZnPorI₂ to DVB ratio, it is possible to optimize the porosity, morphology, and content of Zn-porphyrin. Owing to the synergistic effect of Zn²⁺ and I⁻, the as-prepared ZnPorI₂/30DVB exhibited excellent catalytic activities in the cycloaddition of carbon dioxide with epoxides.

CO₂ hydrogenation to methanol (MeOH) is a key transformation in the Power-to-liquid concept, which aims to store energy in chemical energy carriers and chemicals. Cu/ZnO/ZrO₂ (CZZ) shows great promise due to its enhanced stability in the presence of water, a critical by-product when utilizing CO₂-based feedstocks. The structure-sensitivity of this reaction, especially for particle sizes below 10 nm and in three-component systems, remains highly debated. Herein, we systematically prepared a series of CZZ catalysts by flame spray pyrolysis (FSP) to vary the crystallite size and to study its effect on methanol synthesis in this three-component system. FSP enabled us to maintain a fixed Cu/Zn/Zr ratio close to the commercial composition (61/29/10 atomic ratio), while varying the precursor feed rate. This resulted in variation in the crystallinity. The characterization by X-ray diffraction and electron microscopy revealed an increase in crystallite size with rising feed rate for Cu and t-ZrO₂, whereas ZnO remained mostly unaffected. The testing of the materials in methanol synthesis uncovered an increase in performance, higher space time yield and MeOH selectivity, with decreasing crystallite size for two (Cu, t-ZrO₂) of its three components. The increased selectivity with smaller sizes might be attributed to an increase in interfacial sites.

The serious mismatch between the positive and negative electrodes of supercapacitors (SCs) makes it imperative to develop high-performance negative electrode materials. Among them, multimetallic iron-based oxides (MIBOs) are intensively investigated attributed to their high theoretical specific capacitance, wide operating potential window, copious electrochemical active sites, variable metal oxidation states, and abundant redox centers. This paper briefly introduces some essential information on SCs and the most common synthesis methods of MIBOs. Also, the research progress of several important MIBOs and their composites is discussed. Finally, the existing problems and challenges of MIBOs are summarized and future outlooks are likewise proposed.

Extending the available intramolecularly-stabilised phosphinidene ligands, we report a novel naphthalene supported system derived from readily available starting materials. Specifically, 1,8-bis(diaminophosphino)naphthalene, naphth-1,8-{P(NEt₂)₂}₂ (1), reacts with ethereal HCl to form the mixed diphosphine naphth-1-(PCl₂)-8-{P(NEt₂)₂} 2 as a phosphoranide Zwitterion, which is readily reduced with elemental Mg in forming the target intramolecularly-stabilised phosphinidene 3. The electronic nature of this species is explored through computational DFT, NBO, and TD-DFT analyses, indicating a high electron density at the P^I centre, which delocalizes across the naphthalene ring lending this deep red-purple compound its colour. The coordination capacity of 3 is demonstrated through its reaction with excess CuCl, which surprisingly leads to exclusive formation of the 2 : 1 complex of 3 to Cu, giving initial insights into the coordination chemistry of this novel ligand.

The obtained results reveal simple synthetic approach for bidentate boron Lewis acids with the -OB(C₆F₅)₂ acid group and aliphatic or aromatic linkers. Computational results showed comparable FIA for the -OB(C₆F₅)₂ site in boron bidentate Lewis acids relative to initial B(C₆F₅)₃. The relative Lewis acid strength of R[OB(C₆F₅)₂]₂ (R=C₂H₄, p-C₆H₄, m-C₆H₄) was characterized by Gutman-Beckett tests. The elimination of pentafluorobenzene by the reaction of R-OH with B(C₆F₅)₃ can be used for the synthesis of R-OB(C₆F₅)₂ derivatives and polydentate strong Lewis acids.