Chemistry - A European Journal最新文献

Marine mussels exhibit remarkable adhesive capabilities, providing key inspiration for developing underwater adhesives. However, most existing underwater adhesives fail to replicate the convenient, robust, rapid, and stable adhesion of marine mussels. In this work, we developed a biomimetic underwater adhesive (BMUA) that combines catechol group with solvent-responsive curing mechanism. BMUA was synthesized via a straightforward one-step free radical polymerization in dimethyl sulfoxide (DMSO), using methacrylic acid (MA) and N-isopropylacrylamide (NIPAM) as hydrogen bond (H-bond) components, methyl methacrylate (MMA) as a hydrophobic monomer, and DOPA-functionalized methacrylate as the adhesive unit. Upon water contact, BMUA undergoes solvent exchange rapidly, triggering the formation of a H-bond and hydrophobic crosslinked network. This process effectively displaces interfacial water and enables solidification, resulting in strong underwater adhesion. The BMUA demonstrates high adhesive strength on various substrates under flowing water and maintains robust bonding stability across a range of pH, salinity, and temperature conditions. Notably, BMUA retains efficient adhesion (>1.4 MPa) even after 45 days and shows promising performance in practical applications such as underwater sealing, targeted bonding, and rapid hemostasis in a rat liver injury model. This work offers a new design strategy for high-performance underwater adhesives that closely mimic the advantageous adhesion of marine mussels.

Experimental catalyst design to promote the hydrogenation of CO₂ has led to the synthesis of an efficient tripodal palladium pincer complex. This work presents a computational reading key of the ligand design for efficient transition metal catalysts using palladium pincer complexes as precise representatives. By investigating the electronic structure/reactivity relationship, we demonstrate that all the progressive adjustments of the pincer architecture do not significantly affect the Pd-L (L = PCy₃, PPh₃) bond and the electron density rearrangement in the first coordination sphere of the complex. We find a strong Pd-L bond, where the dispersion energy contribution is substantial, that rules out the previously proposed mechanism involving Pd-L bond breaking. Mechanisms of H₂ activation and CO₂ reduction are revisited, which showcase how the secondary coordination sphere plays a critical role in reactivity, strongly affecting the Pd-O (carboxylic arm) bond polarization due to hydrogen bond formation with the O atom. The catalytically active complex is demonstrated to perform through a stepwise mechanism involving polar addition of H₂ across the Pd^δ+-O^δ- bond and subsequent OH deprotonation by an external base (DBU), forming a Pd-H hydride complex, which easily reacts with CO₂ through an outer-sphere hydride transfer path.

Blatter-type radicals defy conventional chemical expectations, combining unusual stability with intriguing electronic and magnetic properties. We report the first phthalocyanines fused at the periphery with a Blatter-type radical, creating an extended π-conjugated framework. These hybrids merge the characteristic optical and electronic properties of phthalocyanines with a robust, spin-bearing radical, maintaining remarkable stability under ambient conditions. Spectroscopic, crystallographic, and computational studies reveal their distinctive electronic structure, offering insights into radical π-conjugated systems.

Allylic sulfones are valuable structures in bioactive compounds and serve as versatile intermediates in organic synthesis. A selective method for the C-C coupling of aryl sulfones with secondary alcohols has been developed using a Ru-SNS pincer catalyst. This transformation enables efficient access to allylic sulfones under mild conditions with broad functional group tolerance. Sensitive moieties, including olefins and pharmaceutically relevant piperazine-substituted aryl sulfones, are well tolerated. The method demonstrates wide synthetic utility, converting natural product-derived alcohols such as geraniol, nopol, and perillyl alcohol into corresponding sulfone products in high yield. Mechanistic studies suggest the reaction proceeds via initial dehydrogenation of the secondary alcohol to generate a carbonyl intermediate, followed by nucleophilic addition of a sulfone-derived carbanion. A subsequent isomerization step furnishes the allylic sulfone. DFT calculations support this pathway and reveal a key role for the water generated during alcohol oxidation. This in situ formed water facilitates both catalyst regeneration and the final isomerization step, functioning as an essential component in the catalytic cycle. This method provides a practical, atom-economical approach to allylic sulfones with high chemo- and regioselectivity, expanding the toolbox for sulfone chemistry in synthesis and medicinal chemistry applications.

The enantioselective conjugate hydrocyanation of α,β-unsaturated aldehydes remains a long-standing challenge in synthetic chemistry. Here, we report the redesign of 2-deoxy-D-ribose-5-phosphate aldolase (DERA) into an efficient biocatalyst capable of promoting the asymmetric conjugate addition of hydrogen cyanide (generated in situ from trimethylsilyl cyanide) to aromatic enals via an iminium activation pathway. The evolved variant DERA-CN enables the efficient formation of various C4-nitriles with high conversions (up to 99%) and good enantioselectivity (up to 98% e.e.). Control experiments revealed a stepwise process involving enzyme-catalyzed conjugate hydrocyanation followed by spontaneous 1,2-addition of cyanide. Substrates with various electron-donating and electron-withdrawing groups are tolerated, providing access to various enantioenriched nitriles. This work expands the scope of DERA-promoted iminium catalysis and provides a rare enzymatic platform for asymmetric conjugate hydrocyanation under mild aqueous conditions.

Possessing multiple catalytic sites, supramolecular polymers have received attention due to their desirable electrocatalytic activity for ammonia synthesis from NO₃ ^¯. Herein, a covalently cross-linked supramolecular catalytic system (Ru@POP-CD) was synthesized by nucleophilic substitution reaction between ruthenium-coordinated phenanthroline cyclodextrin and tetrafluoroterephthalonitrile, which is not only efficiently electrocatalytic for ammonia synthesis from nitrate but also provides an effective way to combat environmental pollution. Different from noncovalently cross-linked supramolecular polymers, Ru@POP-CD could be kept on the electrode for cycle use and inhibit the hydrogen evolution reaction (HER), achieving a Faradaic efficiency (FE_NH3) of 78.5% at -0.8 V versus RHE in 0.1 M KNO₃/0.1 M KOH solution, with a NH₃ yield rate of 8.72 mg h^-1 cm^-2. This superior electrocatalytic performance is attributed to the unique cyclic structure with rich hydroxyl groups of the cyclodextrin, effective affinity for anionic nitrate through hydrogen bonding and the synergistic interaction of Ru tunable d-orbitals, facilitating the electroreduction of nitrate at the electrode. Meanwhile, in neutral electrolyte (0.1 M KNO₃/0.05 M K₂SO₄), Ru@POP-CD still possesses highly efficient catalytic performance, with the NH₃ yield rate of 7.45 mg h^-1 cm^-2 and FE_NH3 of 83.8% at -0.9 V versus RHE, showing great potential in electrochemical energy supply systems.

The loss of magnetic memory in single-molecule magnets (SMMs) is caused by the coupling of molecular vibrations to spin states, which plays a significant role in magnetic relaxation processes. Gaining direct evidence of vibronic coupling using experimental techniques is critical to understanding and controlling this phenomenon. Most studies focus on assessing the spin-phonon coupling in SMMs to help control this relaxation; herein we gain insight by comparing the SMM [Dy(OPCy₃)₂(H₂O)₅][CF₃SO₃]₃.2(OPCy₃) to the non-SMM [Dy{N(SiMe₃)₂}₃] through collection of far-infrared magnetospectroscopy (FIRMS) spectra and validation with ab initio calculations. Single-crystal measurements display a prominent feature in the spectra at 340 cm^-1, corresponding to an electronic excitation which varies depending on the direction of external magnetic field applied. These findings demonstrate the complicated effect of magnetic anisotropy on the vibronic coupling in SMMs and demonstrate the power of FIRMS to study these effects.

Oxidative additions of C─Hal bonds (Hal  =  F, Cl, Br, I) are widely known for a variety of transition metal complexes owing to their range of oxidation states and flexible coordination sphere. Low valent main group element compounds were shown to mimic this reaction behavior, due to the propensity of changing their oxidation state and coordination number by +2. Yet the addition to C─F bonds is especially challenging due to a large bond dissociation energy. While several examples are known for compounds from group 13 and 14, only few reports demonstrate this type of reaction for compounds from group 15. Herein we report the first anionic P(III) species undergoing an oxidative addition of C─F bonds. The tetracoordinated [P(C₂F₅)₂F₂]^--anion reacts readily with fluorinated arenes, olefins, and acid fluorides yielding respective hexacoordinated P(V) phosphates under mild conditions.

Organic electrode materials (OEMs)-based Dual-ion batteries (DIBs) have emerged as next-generation energy storage technologies due to their high operational voltage, environmental benignity, and cost-effectiveness. Nevertheless, conventional OEMs remain constrained by poor conductivity and insufficient active sites, resulting in inadequate energy/power density for practical applications. This concept focuses on the design and implementation of donor-acceptor (D-A) structured organic electrodes, with a comprehensive review of their performance optimization mechanisms and research advancements in DIBs. Molecular D-A engineering enables precise modulation of electronic structures, energy-level alignment, and charge transport pathways, substantially enhancing electrode redox activity, conductivity, and ion storage kinetics. Finally, the future research directions of DIBs and system compatibility studies are prospected, and a theoretical framework and technical roadmaps for the development of high-energy/power-density organic DIBs are presented.

The electrochemical reduction of CO₂ to valuable chemicals and fuels using bismuth-based catalysts offers a promising pathway toward achieving carbon neutrality. It is widely acknowledged that lattice strain significantly influences the catalytic performance of electrocatalysts in the CO₂ reduction reaction (CO₂RR). Nevertheless, research dedicated to lattice strain engineering in Bi-based catalysts, particularly through the introduction of similar elements from the same group, remains limited. In this work, we rationally designed a bimetallic Bi-Sb catalyst by incorporating Sb into the Bi lattice to induce controlled lattice strain and electronic effects. The optimized Bi₉₉Sb₁ catalyst achieved a peak formate Faradaic efficiency (FE) of 99.4% in a flow cell, maintained FEs above 94.8% over a broad potential window (-0.6 to -1.1 V vs. RHE), and exhibited the highest intrinsic activity. In situ characterizations and density functional theory calculations revealed that Sb doping introduced localized lattice strain while modulating the electronic structure of adjacent Bi sites, thereby strengthening CO₂ adsorption and activation on Bi active centers, reducing the energy barrier for forming the critical *OCHO intermediate. This work highlights the effectiveness of incorporating neighboring metals to tailor lattice strain in Bi-based electrocatalysts, providing a feasible strategy to enhance the catalytic performance of Bi-based electrocatalysts.