European Journal of Inorganic Chemistry最新文献

Investigating the complexation of organic ligands with trivalent lanthanides (Ln(III)) is crucial in various fields, particularly in the separation of actinides from lanthanides for spent fuel reprocessing. While alkyl diamide amine ligands have been extensively studied, aryl-functionalized ligands are rarely reported. To understand the effect of substituents on the coordination mode of diamide amine ligands with Ln(III), two aryl-substituted diamide amine ligands, 2,2′-(p-tolylazanediyl)bis(N-ethyl-N-(p-tolyl)acetamide) (L1) and 2,2′-((2-ethylhexyl)azanediyl)bis(N-ethyl-N-(p-tolyl)acetamide) (L2), were synthesized and systematically studied. ¹H NMR titration showed that metal ion coordination affected the electron density of methylene groups near coordinating atoms more than that of aromatic rings, while fluorescence titration and single-crystal analysis confirmed 1 : 1 ligand-Ln(III) complexes. Compared to alkyl diamide amine ligands, aryl groups increased steric hindrance, enhancing torsional strain and preventing amine nitrogen from participating in complexation, leading to weaker coordination as only two carbonyl oxygen atoms coordinated with Ln(III) in a bidentate mode. This work provides insight into how substituents influence the complexation properties of diamide amine ligands with f-elements, aiding in the design of new ligands with improved performance.

The work presented here investigates whether the Tp^MesFe⁺ moiety, which had been previously found to mediate the dioxygenation of cysteine and cysteamine, can do the same with simple thiols, which are not functionalized by an amine group. Accordingly, the complexes Tp^MesFeSR (R=Ph, ⁱPr) were synthesized and after full characterization exposed to O₂. They were found to react unselectively to yield sulfinates, disulfides, and thiosulfones as products. The sulfinate complex Tp^MesFeO₂S-p-Tol was prepared independently and found to be air-stable, suggesting that the additional products are not formed via overoxidation or subsequent reactions of coordinated sulfinate product. To investigate whether the larger reaction space, opened up due to the missing amine donor is responsible, a Tp-ligand functionalized by a pyridyl donor was employed. A corresponding Tp-iron(II) chlorido complex was prepared and converted through salt metathesis reactions into the respective thiolate analogues, which were fully characterized and structurally authenticated. However, subsequent O₂ reactivity studies did not show an improved selectivity. The reason may lie in a more open reaction pocket in combination with an electronic situation which is less ideal than in case of Tp^MesFe(cysteamine).

Grasping the behavior of metal nanoclusters in solution at the atomic level is a pinnacle challenge in nanoscience. In addressing this, our work utilizes the Ag₁₃@Ag₁₆(BDT)₁₂(TPP)₄ (Ag₂₉) nanocluster (where BDT represents 1,3-benzenedithiol, and TPP is triphenylphosphine) as a template. We employ isotopic layering labeling, such as a¹⁰⁹ Ag₁₃@¹⁰⁷ Ag₁₆ core -shell structure, to mark the clusters. Subsequently, we conduct reactions with clusters featuring two different layering structures. Finally, we employ isotopic labeling to replace Ag in the shell, followed by analysis using ESI-MS, enabling us to discern the process of intercluster reactions. We observed that the reactions primarily involve metal exchanges between the cores of different clusters and separately between their shells, highlighting distinct patterns of atomic-level exchanges within these structures. This study thus offers pivotal insights into the molecular-level mechanisms of metal exchange between clusters, significantly contributing to the development of metal nanocluster design and synthesis.

The Front Cover shows a sterically hindered copper(I) phenanthroline complex. Such steric hindrance leads to an optimization of the ground-state and excited-state properties. The background shows the skyline of Strasbourg (France) and to the left of the image, the chemistry tower where the first copper(I) phenanthroline complex was synthesised by Prof. Jean-Pierre Sauvage and his group; to whom this paper is dedicated. More information can be found in the Research Article by C. Gourlaouen, R. Ruppert, M. Mauro and co-workers.

The Cover Feature depicts two of four lowest energy conformational isomers of ortho-phosphinophenol predicted by theory. Interestingly, these two particular isomers reflect intramolecular forms of attractive P⋅⋅⋅HO hydrogen bonding (HB) or PH₂⋅⋅⋅HO dihydrogen bonding (DHB) withing the same molecule. In the gas phase, the isomer possessing bifurcated DHB is predicted to be lower in energy than the isomer with HB. Experimental evidence supports the existence of a) multiple isomers in solution (solution-phase IR spectral data), b) the presence of intermolecular P⋅⋅⋅HO HB in the solid state (single-crystal X-ray structure), and c) the presence of substantial intermolecular OH⋅⋅⋅S HB (S=solvent lone pair or π-system) interactions in solution (³¹P NMR spectral data). More information can be found in the Research Article by J. D. Protasiewicz and co-workers.

The Kumada-Corriu hetero-coupling between an halogeno-arene and an arylmagnesiumbromide can be catalyzed with yields >80 % by the new hydrotris(3,5-diisopropylpyrazolyl)boratocobalt(III)diiodide, i. e. Tp^iPrCoI₂. The catalysis, which is significantly improved upon exposure to light as compared to darkness, is determined by the coexistence of low and high spin states in a respective ratio of ~3 : 2 for the crucial “Tp^iPrCoAr₂” intermediate. The pivotal cobalt(I) Tp^iPrCo^(I)(thf)_n intermediate is shown to be exclusively a triplet state in the ground state with a measured μ_eff value of 3.08 μ_B at 293 K in C₆D₆. DFT investigations confirm the key role of triplet states for the bisaryl-cobalt(III) intermediates in that they provide a reaction pathway with much lower activation barriers as compared to the singlet state. The low-to-high spin state transition in THF enhances the reactivity of the “Tp^iPrCoAr₂” intermediate, which changes its coordination geometry from singlet spin state 18 electron OC-6 Tp^iPrCoAr₂(thf) to a triplet spin state 16 electron SPY-5 Tp^iPrCoAr₂ where the Tp^iPr ligand adopts a nearly κ² bonding mode. The quantitative Independent Gradient Model analysis of the noncovalent interactions that prefigure the C−C covalent bond in the key Co(Ar)₂ intermediates informs of the peculiar importance of the singlet to triplet spin state crossover in catalysis.

Unusual open-chain tetradentate NHC-phosphine pre-ligand [Ph₂PCH(Ph)ImCH₂ImC(H)PhPPh₂](BF₄)₂ was prepared in a good yield by metal-mediated approach starting from Mn(I) complex [Cp(CO)₂Mn(η²-Ph₂P=C(H)Ph)](BF₄) and bis(imidazole) derivative ImCH₂Im. Its reaction with Pd(OAc)₂ afforded dicationic Pd(II) complex of bis(NHC)bis(phosphine) ligand adopting κ⁴PĈĈP coordination mode as a mixture of two diastereomers. The deprotonation of the C(H)Ph ligand bridge in the latter using KN(SiMe₃)₂ as base provided stable complex exhibiting unconventional phosphonium ylide moiety, whereas all attempts to detect the corresponding bis(ylide) derivative failed.

This study successfully synthesized a new Metal-Organic Framework (MOF) named CJLU−L2, which was constructed from phosphorus-containing ligands and Co(II) ions. The structure revealed through single-crystal X-ray diffraction (SCXRD), features a double-walled honeycomb-shaped structure with a one-dimensional channel of ~6.5 Å. According to the PLATON calculation, the pore volume per unit cell of CJLU−L2 was determined to be 6825.0 ų, constituting 57.5 % of the total crystal volume (11874.9 ų). The Brunauer-Emmett-Teller (BET) surface area of CJLU−L2 was determined to be 954 m²/g by N₂ adsorption measurement at 77 K. The phase purity of CJLU−L2 was verified by powder X-ray diffraction (PXRD) and infrared spectroscopy (IR), while its thermal stability was confirmed by thermogravimetric analysis (TGA). Hydrogen adsorption experiments demonstrate that CJLU−L2 exhibits a high hydrogen adsorption capacity, indicating significant potential for gas adsorption applications.