European Journal of Inorganic Chemistry最新文献

The crystal structures of three compounds derived from the reduction of Mn₂(CO)₁₀ with potassium in liquid ammonia solution with and without the presence of [2.2.2]crypt ([2.2.2]crypt = 4,7,13,16,21,24-Hexaoxa-1,10-diazabicyclo[8.8.8]-hexacosane) is reported. For the formation of [K([2.2.2]crypt)]₂[HMn(CO)₄] 2 NH₃ and K₃[Mn(CO)₄] 2 NH₃, liquid ammonia plays a crucial role as a solvent providing solvated electrons used for the reduction as well as for the stabilization of highly charged manganese carbonylates in ammoniate crystals. The isolation of [K([2.2.2]crypt)][Mn(CO)₄(NH₃)] 3 NH₃ offers an insight into a possible intermediate during the reduction from [Mn(CO)₅]⁻ to [Mn(CO)₄]³⁻ via the ammonia alkali metal route.

Porphyrin derivatives have been widely studied as models for (bacterio)chlorophyll pigments, and various dimeric architectures have been constructed through covalent or noncovalent bonds to mimic the special pairs found in photosynthetic reaction centers. Herein, novel cyclic porphyrin dimers are reported that are formed through the coordination between meso-substituted porphyrins bearing two phosphine oxide groups and lanthanide complexes, Ln(hfa)₃ (Ln = Yb, Lu; hfa = hexafluoroacetylacetonate). Single-crystal X-ray analysis of the Yb(III) complex revealed a slipped cofacial arrangement, in which two porphyrin units are bridged by Yb(III) centers via phosphine oxide coordination, closely resembling natural special pairs. The resulting dimers are stable in toluene and exhibit broadened Soret bands and redshifted Q bands compared to the monomeric porphyrin ligand. Upon porphyrin photoexcitation, the Yb(III) complex shows near-infrared luminescence from the Yb(III) center, while the porphyrin fluorescence intensity is essentially unaffected, demonstrating potential for oxygen sensing (Φ_Yb(Ar)/Φ_Yb(air) = 4.8). Transient absorption measurements confirmed the extended T₁ lifetime of the porphyrin units within the dimer structure. The dimers also show enhanced photostability under blue-light irradiation compared to the monomer. This study presents the first example of the Yb(III)-coordinated slipped cofacial porphyrin dimer with ratiometric oxygen-sensing capability and high photostability.

The Front Cover shows eight uranyl phosphonate and arsonate nanotubules and nanospheres. These materials represent a diverse family of self-assembling nanoscale structures, whose topological variety, intricate architectures, and functional properties arise from continued advances in synthetic chemistry. The Review by P. O. Adelani (DOI: 10.1002/ejic.202500222) highlights three decades of research aimed at understanding actinide materials for nuclear waste disposal and advanced nuclear fuel cycles.

The energetics and mechanisms of cyclocondensation reactions between SeCl₂ and ^tBuNH₂ in 1:3 molar ratio are examined using density functional theory with implicit solvation in tetrahydrofuran at 193 K. The results give strong support for the proposed stepwise pathway consisting of three key steps: 1) formation of an acyclic building block ^tBuN(H)SeCl, 2) chain growth to ClSe[N(^tBu)Se]_nCl (n = 1–3, 7–9), and 3) ring closure to 1,3,5-Se₃(N^tBu)₃ (1), 1,3,5,7-Se₄(N^tBu)₄ (2), 1,3-Se₃(N^tBu)₂ (3), or 1,3,5-Se₄(N^tBu)₃ (4). The paths leading to 3 and 4 include additional redox steps and diradical intermediates to generate SeSe bonds. The proposed paths share common intermediates, which allows the rationalization of the experimental product distribution as well as changes to it upon altering the stoichiometry or the total SeCl₂ concentration. The results further show that the successive addition of [N(^tBu)Se] units quickly becomes energy neutral, decreasing the likelihood for the formation of molecules with more than eight atoms by cyclocondensation. Plausible mechanisms explaining the formation of the 15-membered ring 1,3,6,8,11,13-Se₉(N^tBu)₆ (5) involve the coupling of diradical intermediates or redox processes converting SeCl₂ to Se₂Cl₂, both of which might also play a role in the generation of SeSeSe functionalities in 1,5-Se₆(N^tBu)₂ (6).

The Front Cover shows a ruthenium arene-based compound, a new metal-based cancer drug that shows promise due to unique mechanisms and better targeting of cancer cells than early treatments like cisplatin. Ruthenium(II) arene scaffolds have emerged as suitable candidates due to their ligand substitution ability, selectivity, lower toxicity, and stability compared to traditional platinum-based drugs like cisplatin. More information can be found in the Research Article by S. Maji and co-workers (DOI: 10.1002/ejic.202500300).

The catalytic dehydrocoupling of amine boranes produces well-defined BN compounds and polymers that are isovalent electronic to hydrocarbon analogs. In this study, the synthesis and characterization of a set of Rh, Ir, and Ru complexes with tridentate imidazolylphosphine PN(H)N ligands of the type (imidazolyl)CH₂N(H)CH₂CH₂PR₂ (R = iPr, tBu) are presented. These complexes potentially engage in metal–ligand cooperative dehydrogenation of amine boranes, followed by BN coupling. All complexes show facial coordination of the PN(H)N ligands to the metal centers with pronounced hydrogen bonding to an outer-sphere chloride ligand. All Rh and Ir complexes are active catalysts for the dehydrogenation of H₃B·NMeH₂ and H₃B·NMe₂H, producing mainly linear and cyclic BN oligomers. Only the Ru complex [Ru(PN(H)N)(PPh₃)(CO)(H)]Cl (8) produces low-molecular-weight poly(aminoboranes) from H₃B·NMeH₂ with high activity after activation with KOtBu, supporting metal-ligand cooperativity during activation of the amine borane substrates.

The conversion and utilization of carbon dioxide (CO₂) is a challenging contemporary issue in the present day, and the first step is the CO₂ fixation. Recently, the main group metal compounds have been found that have the analogous reactivity to transition metals and are capable of activating inert small molecules. In this work, the reaction mechanisms of [Al-M] (M = Zn, Be, Mg, and Ca) heterobimetallic compounds with CO₂ are investigated by density functional theory calculations. The calculated results indicate that the bimetallic main group compounds [AlAe] (Ae = Be, Mg, Ca) show similar activities near to that of [AlZn] and they can activate CO₂ at low temperature due to the low energy barriers. For both [AlAe] and [AlZn], AlC bond mode is the thermodynamic control and AlO bond mode is kinetic control pathway. At experimental conditions, AlC bond mode is the main reaction pathway for [AlAe], whereas for [Al-Zn], AlO bond mode is preferred. The reactivity is depended on AlM bond strength, the weaker AlM bond, the more reactivity of [Al-M] is.

Metallo-β-lactamases (MβLs) are bacterial Zn²⁺ dependent enzymes that catalyze the hydrolysis inactivating β-lactam antibiotics. Understanding their mechanism is crucial for developing more potent antibiotics and for designing inhibitors of MβLs paving the way for more effective treatments. To this end, numerous Zn²⁺ complexes that mimic MβLs have been synthesized and studied, leading to the conclusion that often a hydroxyl group coordinated to Zn²⁺ is responsible for the hydrolysis of substrates. In parallel, research on MβLs has highlighted the importance of the coordination of the substrate to Zn²⁺ and the involvement of the reactive hydroxyl group or of a water molecule in hydrogen bonding to facilitate the hydrolysis. The development of more suitable biomimetic complexes of MβL, which replicate these enzymatic features, can become crucial for obtaining deeper and more accurate mechanistic insights.

The synthesis and anticancer evaluation of palladium(II) complexes bearing mannose-conjugated mesoionic carbenes and their triazolium precursors (triazolium palladates) is reported. Ligand precursors are easily obtained via copper-catalyzed azide–alkyne cycloaddition. Palladium allyl carbene complexes are prepared extending the weak base route protocol to triazolium salts by reacting the metal precursor and azolium salts with potassium carbonate as the base in acetonitrile and under mild conditions. Additionally, triazolium allyl palladates are isolated, which represent the first examples of triazolium palladate complexes described in the literature. In vitro tests on a panel of cancer cell lines (A2780, A2780cis, DLD-1) reveal better or comparable cytotoxicity to cisplatin. The majority of complexes exhibit low cytotoxicity (>100 μM) toward MRC-5 and FT-190 nontumoral cell lines demonstrating remarkable in vitro selectivity.

Flexible and luminescent Red-emissive films based on thermoplastic polyurethane (TPU) doped with different % wt of the europium complex Eu(TTA)₃bipy have been developed. A complete characterization was carried out by spectroscopic techniques, thermal analysis, AFM and SEM microscopy and X-ray diffraction; this allowed the interaction present in the materials to be understood. Interestingly, even with low concentrations, bright red emission with a QY close to 17% was achieved. Further details can be found in the Research Article by P. Fuentealba, Y. Gil and co-workers (DOI: 10.1002/ejic.202500018). The authors thank the Fondo Apoyo Pago de Publicaciones Científicas de la DI&DITT-FaCiQyF for financial support.