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A Crosslinked Ionic Organic Framework for Efficient Iodine and Iodide Remediation in Water

A Crosslinked Ionic Organic Framework for Efficient Iodine and Iodide Remediation in Water

An ionic porous organic framework (HCOF-7) has been developed to remove iodine residues (I2 and I) after water disinfection, demonstrating high breakthrough volumes and wide working temperatures.

Abstract

Iodine is widely used as an antimicrobial reagent for water disinfection in the wilderness and outer space, but residual iodine and iodide need to be removed for health reasons. Currently, it is challenging to remove low concentrations of iodine and iodide in water (≈5 ppm). Furthermore, the remediation of iodine and iodide across a broad temperature range (up to 90 °C) has not previously been investigated. In this work, we report a nitrate dimer-directed synthesis of a single-crystalline ionic hydrogen-bonded crosslinked organic framework (HCOF-7). HCOF-7 removes iodine and iodide species in water efficiently through halogen bonding and anion exchange, reducing the total iodine concentration to 0.22 ppm at room temperature. Packed HCOF-7 columns were employed for iodine/iodide breakthrough experiments between 23 and 90 °C, and large breakthrough volumes were recorded (≥18.3 L g−1). The high iodine/iodide removal benchmarks recorded under practical conditions make HCOF-7 a promising adsorbent for water treatment.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Mingshi Zhang, Jayanta Samanta, Benjamin A. Atterberry, Richard Staples, Aaron J. Rossini, Chenfeng Ke
onlinelibrary.wiley.com/doi/10.1002/anie.202214189

Spin‐Selective Charge Transport in Lead‐Free Chiral Perovskites: The Key towards High‐Anisotropy in Circularly‐Polarized Light Detection

Spin-Selective Charge Transport in Lead-Free Chiral Perovskites: The Key towards High-Anisotropy in Circularly-Polarized Light Detection

A pair of zero-dimensional bismuth-based chiral perovskites has been introduced towards the detection of circularly polarized light. The lower dimensional perovskites exhibit high degree of chirality-induced spin-selectivity allowing the transport of one type of spin-half state while blocking the other type resulting in an anisotropic current response of the photodetectors that can be used to detect the polarization state of CPL photons.

Abstract

A pair of zero-dimensional lead-free chiral perovskites is introduced towards the detection of circularly polarized light (CPL). Although spin-polarized carriers are generated in the perovskites under the CPL, the absorption anisotropy remained low leading to mostly similar density of photogenerated carriers under the two CPLs. Interestingly, due to the intrinsic chirality in the perovskites, they exhibited chirality-induced spin-selectivity (CISS) allowing the transport of only one type of spin-half states. A high anisotropy in photocurrent along the out-of-plane direction has therefore appeared resulting in a spin-dependent photovoltaic effect in vertical heterojunction devices and making them suitable for CPL detection. While a self-powered CPL detector showed a limited (but one of the highest to date) anisotropy factor of 0.3 due to possible spin-flips during the transport process, the factor rose to 0.6 under bias prompting extension of the effective spin-diffusion length.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Abhishek Maiti, Amlan J. Pal
onlinelibrary.wiley.com/doi/10.1002/anie.202214161

Enhanced Acidic Water Oxidation by Dynamic Migration of Oxygen Species at the Ir/Nb2O5−x Catalyst/Support Interfaces

Enhanced Acidic Water Oxidation by Dynamic Migration of Oxygen Species at the Ir/Nb2O5−x Catalyst/Support Interfaces

The dynamic migration of oxygen species between oxide support and Ir catalyst during OER is uncovered. These migrations not only regulate the in situ Ir catalytic structure towards boosted activity, but also suppresses Ir over-oxidation via oxygen species transference, thereby ensuring overall high performance in PEM water electrolyzer.

Abstract

Catalyst/support interaction plays a vital role in catalysis towards acidic oxygen evolution (OER), and the performance reinforcement is currently interpreted by either strain or electron donation effect. We herein report that these views are insufficient, where the dynamic evolution of the interface under potential bias must be considered. Taking Nb2O5−x supported iridium (Ir/Nb2O5−x) as a model catalyst, we uncovered the dynamic migration of oxygen species between IrO x and Nb2O5−x during OER. Direct spectroscopic evidence combined with theoretical computation suggests these migrations not only regulate the in situ Ir structure towards boosted activity, but also suppress its over-oxidation via spontaneously delivering excessive oxygen from IrO x to Nb2O5−x. The optimized Ir/Nb2O5−x thus demonstrated exceptional performance in scalable water electrolyzers, i.e., only need 1.839 V to attain 3 A cm−2 (surpassing the DOE 2025 target), and no activity decay during a 2000 h test at 2 A cm−2.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Zhaoping Shi, Ji Li, Jiadong Jiang, Yibo Wang, Xian Wang, Yang Li, Liting Yang, Yuyi Chu, Jingsen Bai, Jiahao Yang, Jing Ni, Ying Wang, Lijuan Zhang, Zheng Jiang, Changpeng Liu, Junjie Ge, Wei Xing
onlinelibrary.wiley.com/doi/10.1002/anie.202212341

Multilayered Ceramic Membrane with Ion Conducting Thin Layer Induced by Interface Reaction for Stable Hydrogen Production

Multilayered Ceramic Membrane with Ion Conducting Thin Layer Induced by Interface Reaction for Stable Hydrogen Production

Inspired by the architectural structure of the rooted grasses in soil, an interface-reaction-induced reassembly approach for the direct fabrication of ion-conducting thin layers rooted in multilayered ceramic membranes has been developed. This novel technique paves the way for the development of high-performance multilayered ceramics with functional layers for various applications, from ceramic fuel cells and membrane reactors to gas sensors.

Abstract

Conventional methods for fabricating multilayered ceramic membranes with ion conducting dense thin layers are often cumbersome, costly, and limited by poor adhesion between layers. Inspired by the architectural structure of the rooted grasses in soil, here, we report an interface-reaction-induced reassembly approach for the direct fabrication of Ce0.9Gd0.1O2−δ (CGO) thin layers rooted in the parent multilayered ceramic membranes by only one firing step. The CGO dense layers are very thin, and adhered strongly to the parent support layer, ensuring low ionic transport resistance and structural integrity of the multilayered membranes. When using as an oxygen permeable membrane for upgrading fossil-fuel-derived hydrogen, it shows very long durability in harsh conditions containing H2O, CH4, H2, CO2 and H2S. Furthermore, our approach is highly scalable and applicable to a wide variety of ion conducting thin layers, including Y0.08Zr0.92O2−δ, Ce0.9Sm0.1O2−δ and Ce0.9Pr0.1O2−δ.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Guanghu He, Qianqian Lan, Mengke Liu, Guixuan Wu, Rafal E. Dunin‐Borkowski, Heqing Jiang
onlinelibrary.wiley.com/doi/10.1002/anie.202210485

Tumor‐Selective Activation of Toll‐Like Receptor 7/8 Agonist Nano‐Immunomodulator Generates Safe Anti‐Tumor Immune Responses upon Systemic Administration

Tumor-Selective Activation of Toll-Like Receptor 7/8 Agonist Nano-Immunomodulator Generates Safe Anti-Tumor Immune Responses upon Systemic Administration

To overcome the uncontrolled off-target systemic immune-related adverse effects (irAEs) of imidazoquinolines after systemic administration, we developed a nano-immunomodulator (cN@SS-IMQ) that is inactive until it is selectively metabolized to an active immunostimulant within tumor cells. cN@SS-IMQ promoted robust immune activation within tumors while limiting extra-tumoral stimulation, suggesting its promising potential for systemically targeting innate immune tumor stimulators.

Abstract

Agonists of innate pattern recognition receptors such as toll-like receptors (TLRs) prime adaptive anti-tumor immunity and hold promise for cancer immunotherapy. However, small-molecule TLR agonists cause immune-related adverse effects (irAEs) after systemic administration. Herein, we report a polymeric nano-immunomodulator (cN@SS-IMQ) that is inactive until it is selectively metabolized to an active immunostimulant within the tumor. cN@SS-IMQ was obtained via self-assembly of a cyclo(Arg-Gly-Asp-D-Phe-Lys)-modified amphiphilic copolymeric prodrug. Upon systemic administration, cN@SS-IMQ preferentially accumulated at tumor sites and responded to high intracellular glutathione levels to release native imidazoquinolines for dendritic cell maturation, thereby enhancing the infiltration of T lymphocytes. Collectively, cN@SS-IMQ tends to activate the immune system without irAEs, thus suggesting its promising potential for safe systemic targeting delivery.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Yanyun Hao, Hui Li, Xiaoyan Ge, Yang Liu, Xia Li, Yutong Liu, Hongfei Chen, Shiying Zhang, Jing Zou, Lingling Huang, Fabao Zhao, Dongwei Kang, Bruno G. De Geest, Zhiyue Zhang
onlinelibrary.wiley.com/doi/10.1002/anie.202214992

Revealing the High Salt Concentration Manipulated Evolution Mechanism on the Lithium Anode in Quasi‐Solid‐State Lithium‐Sulfur Batteries

Revealing the High Salt Concentration Manipulated Evolution Mechanism on the Lithium Anode in Quasi-Solid-State Lithium-Sulfur Batteries

The electrochemical processes at the Li anode/electrolyte interface are disclosed in quasi-solid-state lithium-sulfur batteries with high salt concentration via in-situ atomic force microscopy and optical microscopy. The 3D morphology, local mechanics, and ion conductivity of the on-site formed solid electrolyte interphase are in-situ measured and analyzed to reveal the regulation effect of high salt concentration on interfacial electrochemistry.

Abstract

Lithium-sulfur batteries are promising candidates of energy storage devices. Both adjusting salt/solvent ratio and applying quasi-solid-state electrolytes are regarded as effective strategies to improve the lithium (Li) anode performance. However, reaction mechanisms and interfacial properties in quasi-solid-state lithium-sulfur (QSSLS) batteries with high salt concentration are not clear. Here we utilize in-situ characterizations and molecular dynamics simulations to unravel aforesaid mysteries, and construct relationships of electrolyte structure, interfacial behaviour and performance. The generation mechanism, formation process, and mechanical/chemical/electrochemical properties of the anion-derived solid electrolyte interphase (SEI) are deeply explored. Li deposition uniformity and dissolution reversibility are further tuned by the sustainable SEI. These straightforward evidences and deepgoing studies would guide the electrolyte design and interfacial engineering of QSSLS batteries.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Gui‐Xian Liu, Jian‐Xin Tian, Jing Wan, Yuan Li, Zhen‐Zhen Shen, Wan‐Ping Chen, Yao Zhao, Fuyi Wang, Bing Liu, Sen Xin, Yu‐Guo Guo, Rui Wen
onlinelibrary.wiley.com/doi/10.1002/anie.202212744

A Sulfoxide Reagent for One‐Pot, Three‐Component Syntheses of Sulfoxides and Sulfinamides

A Sulfoxide Reagent for One-Pot, Three-Component Syntheses of Sulfoxides and Sulfinamides**

Upon Grignard reactions, a simple sulfoxide reagent allows the formation of sulfenate anions that are subsequently transformed into sulfoxides and sulfinamides. This one-pot, three-component method does not require substrates with preinstalled sulfur functional groups.

Abstract

Sulfoxides and sulfinamides represent versatile sulfur functional groups found in ligands, chiral auxiliaries, and bioactive molecules. Canonical two-component syntheses, however, rely on substrates with a preinstalled C−S bond and impede efficient and modular access to these sulfur motifs. Herein is presented the application of an easily prepared, bench-stable sulfoxide reagent for one-pot, three-component syntheses of sulfoxides and sulfinamides. The sulfoxide reagent donates the SO unit upon the reaction with a Grignard reagent (RMgX) as a sulfenate anion (RSO). While subsequent trapping reactions of this key intermediate with carbon electrophiles provide sulfoxides, a range of tertiary, secondary, and primary sulfinamides can be prepared by substitution reactions with electrophilic amines. The syntheses of sulfinamide analogs of amide- and sulfonamide-containing drugs illustrate the utility of the method for the rapid preparation of medicinally relevant molecules.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Fumito Saito
onlinelibrary.wiley.com/doi/10.1002/anie.202213872

Observation of an Alternate Charge‐Polarization State in a One‐Dimensional Pt−Pt−I Chain Compound with a Bulky Pendant Ligand

Observation of an Alternate Charge-Polarization State in a One-Dimensional Pt−Pt−I Chain Compound with a Bulky Pendant Ligand

The synthesis and physical properties of a new one-dimensional (1D) halogen-bridged dinuclear-metal complex (MMX-chain) with a rigid and bulky pendant ligand are reported. The steric hindrance derived from the bulkiness induces a strain in its 1D chain, achieving the first pure electronic state coupled with lattice distortion at ambient condition. The strain effect also appears as a very large linear thermal expansion along the 1D chain.

Abstract

A one-dimensional (1D) halogen-bridged dinuclear-metal complex (MMX-chain) exhibits various electronic states based on a mixed-valence metal-dimer system. This report deals with the synthesis and physical properties of a new MMX-chain with a bulky pendant ligand, Pt2(mcc-HexCS2)4I (mcc-HexCS2=trans-4-(methoxycarbonyl)cyclohexanedithiocarboxylate). The steric hindrance caused by the bulky substituent induces a strain in its 1D chain, achieving at ambient condition the first pure alternate charge-polarization (ACP) state (−Pt2+−Pt3+−I−Pt3+−Pt2+−I−), a kind of spin-Peierls state, as confirmed by X-ray diffraction and its conducting and magnetic properties. The strain effect is also manifested as a very large linear thermal expansion along the chain direction, which is quite different from conventional MMX-chains without a bulky ligand. The design of low-dimensional materials with ligand variations is expected to lead to the emergence of new electron–lattice coupled electronic states.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Hayato Moriyama, Kazuya Otsubo, Kunihisa Sugimoto, Shogo Kawaguchi, Hiroshi Kitagawa
onlinelibrary.wiley.com/doi/10.1002/anie.202214108

Sustainable Conversion of Microplastics to Methane with Ultrahigh Selectivity by a Biotic–Abiotic Hybrid Photocatalytic System

Sustainable Conversion of Microplastics to Methane with Ultrahigh Selectivity by a Biotic–Abiotic Hybrid Photocatalytic System

Methanogen-semiconductor biohybrids drive sustainable conversion of microplastics to CH4 under illumination. This addresses a long-standing challenge of photocatalysis by fully utilizing photogenerated electrons and holes without the need of using expensive and unsustainable chemical sacrificial quenchers.

Abstract

Efficient conversion of microplastics into fuels provides a promising strategy to alleviate environmental pollution and the energy crisis. However, the conventional processes are challenged by low product selectivity and potential secondary pollution. Herein, a biotic-abiotic photocatalytic system is designed by assembling Methanosarcina barkeri (M. b) and carbon dot-functionalized polymeric carbon nitrides (CDPCN), by which biodegradable microplastics—poly(lactic acid) after heat pretreatment can be converted into CH4 for five successive 24-day cycles with nearly 100 % CH4 selectivity by the assistance of additional CO2. Mechanistic analyses showed that both photooxidation and photoreduction methanogenesis worked simultaneously via the fully utilizing photogenerated holes and electrons without chemical sacrificial quenchers. Further research validated the real-world applicability of M. b-CDPCN for non-biodegradable microplastic-to-CH4 conversion, offering a new avenue for engineering the plastic reuse.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Jie Ye, Yiping Chen, Chao Gao, Chao Wang, Andong Hu, Guowen Dong, Zhi Chen, Shungui Zhou, Yujie Xiong
onlinelibrary.wiley.com/doi/10.1002/anie.202213244

Dithiol‐Activated Bioorthogonal Chemistry for Endoplasmic Reticulum‐Targeted Synergistic Chemophototherapy

Dithiol-Activated Bioorthogonal Chemistry for Endoplasmic Reticulum-Targeted Synergistic Chemophototherapy

Bioorthogonal chemistry is introduced for design of organic nitrite donors, on the basis of SNAr and cyclization reactions between dithiols and 5-nitrobenzo[c][2,1,3]thiadiazole derivatives. A combination of “click to release” strategy and photoactivation is achievable for cancer chemophototherapy.

Abstract

The controlled intracellular release of nitrite is still an unmet challenge due to the lack of bio-friendly donors, and the antitumor effect of nitrite is limited by its physiologically inert activity. Herein, we designed benzothiadiazole-based organic nitrite donors that are stable against bio-relevant species but selectively respond to dithiol species through SNAr/intramolecular cyclization tandem reactions in the aqueous media. The bioorthogonal system was established to target the endoplasmic reticulum (ER) of liver cancer HepG2 cells. The nitrite and nonivamide were coupled to induce elevation of intracellular levels of calcium ions as well as reactive oxygen/nitrogen species, which resulted in ER stress and mitochondrial dysfunction. We demonstrated that a combination of photoactivation and “click to release” strategy could enhance antitumor effect in cellular level and show good potential for cancer precision therapy.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Jian Sun, Xiaoran Zhang, Xia Wang, Jinlei Peng, Gang Song, Yufei Di, Fude Feng, Shu Wang
onlinelibrary.wiley.com/doi/10.1002/anie.202213765

Organocatalyzed Controlled Radical Copolymerization toward Hybrid Functional Fluoropolymers Driven by Light

Organocatalyzed Controlled Radical Copolymerization toward Hybrid Functional Fluoropolymers Driven by Light

A metal-free controlled radical copolymerization of trifluorovinyl boronic ester and vinyl esters has been established, enabling the on-demand synthesis of main-chain hybrid functional polymers driven by light. This work furnishes a facile and versatile strategy to tailor F/B-incorporated polymers, which facilitates chain-extensions, post modifications to unprecedented polymers, and allows innovations of copolymer electrolytes.

Abstract

Photo-controlled polymerizations are attractive to tailor macromolecules of complex compositions with spatiotemporal regulation. In this work, with a convenient synthesis for trifluorovinyl boronic ester (TFVB), we report a light-driven organocatalyzed copolymerization of vinyl monomers and TFVB for the first time, which enabled the controlled synthesis of a variety of hybrid fluorine/boron polymers with low dispersities and good chain-end fidelity. The good behaviors of “ON/OFF” switch, chain-extension polymerizations and post-modifications further highlight the versatility and reliability of this copolymerization. Furthermore, we demonstrate that the combination of fluorine and boron could furnish copolymer electrolytes of high lithium-ion transference number (up to 0.83), bringing new opportunities of engineering high-performance materials for energy storage purposes.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Yang Zeng, Qinzhi Quan, Peng Wen, Zexi Zhang, Mao Chen
onlinelibrary.wiley.com/doi/10.1002/anie.202215628

Fabricating Industry‐Compatible Olefin‐Linked COF Resins for Oxoanion Pollutant Scavenging

Fabricating Industry-Compatible Olefin-Linked COF Resins for Oxoanion Pollutant Scavenging

Neutral and ionic vinylene-linked covalent organic frameworks (COFs) were constructed with inexpensive 2,4,6-collidine as the building unit by a melt polymerization method. The as-prepared, low-cost cationic COF foams showed high crystallinity, abundant porosity, superior stability, and high adsorption capacity for oxoanion pollutants. This study opens a pathway to large-scale industrial production of ionic COFs.

Abstract

Large-scale and low-cost synthesis of covalent organic frameworks (COFs) to meet the demands of industrial application remains formidably challenge. Here we report using 2,4,6-collidine as monomer to produce a series of highly crystalline olefin-linked COFs by a melt polymerization method. This method enables the kilogram-scale fabrication of self-shaped monolithic robust foams. The afforded COFs possess extremely low cost (<50 USD/kg), superior to all the reported COFs. Furthermore, using one-pot or post-modification methods can conveniently transform neutral COFs to ionic COFs, which can be applied as highly efficient ion-exchange sorbents for scavenging oxoanion pollutants. Remarkably, the superior adsorption capacity of a model oxoanion (ReO4) is the highest among crystalline porous materials reported so far. This work not only expands the scopes of olefin-linked COFs but also enlightens the route for the industrial production of crystalline ion exchange sorbents.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Penghui Zhang, Zhifang Wang, Sa Wang, Jian Wang, Jinjin Liu, Ting Wang, Yao Chen, Peng Cheng, Zhenjie Zhang
onlinelibrary.wiley.com/doi/10.1002/anie.202213247

Bifunctional Europium for Operando Catalyst Thermometry in an Exothermic Chemical Reaction

Bifunctional Europium for Operando Catalyst Thermometry in an Exothermic Chemical Reaction

Temperature determines the reaction kinetics, thermodynamics and catalyst stability. However, very limited information is known about the local catalyst temperature. Here, operando thermometry over bifunctional Eu3+ is performed to study the interplay between reaction conditions and the catalyst temperature dynamics in the exothermic methane oxychlorination reaction.

Abstract

Often the reactor or the reaction medium temperature is reported in the field of heterogeneous catalysis, even though it could vary significantly from the reactive catalyst temperature. The influence of the catalyst temperature on the catalytic performance and vice versa is therefore not always accurately known. We here apply EuOCl as both solid catalyst and thermometer, allowing for operando temperature determination. The interplay between reaction conditions and the catalyst temperature dynamics is studied. A maximum temperature difference between the catalyst and oven of +16 °C was observed due to the exothermicity of the methane oxychlorination reaction. Heat dissipation by radiation appears dominating compared to convection in this set-up, explaining the observed uniform catalyst bed temperature. Application of operando catalyst thermometry could provide a deeper mechanistic understanding of catalyst performances and allow for safer process operation in chemical industries.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Bas J. P. Terlingen, Tjom Arens, Thomas P. Swieten, Freddy T. Rabouw, P. Tim Prins, Michiel M. Beer, Andries Meijerink, Mathieu P. Ahr, Eline M. Hutter, Coert E. J. Lare, Bert M. Weckhuysen
onlinelibrary.wiley.com/doi/10.1002/anie.202211991

In Situ Enzyme Immobilization by Covalent Organic Frameworks

In Situ Enzyme Immobilization by Covalent Organic Frameworks

Y. Chen and co-workers recently expanded the range of crystalline porous solids for the in situ encapsulation of enzymes to covalent organic frameworks (COFs). The designed enzyme@COF biocatalyst exhibited high enzyme loading with minimal leaching, high catalytic activity and selectivity, chemical and long-term stability, and recyclability while also allowing a scale-up to a few grams.

Abstract

Enzyme immobilization is a widely reported method to favor the applicability of enzymes by enhancing their stability and re-usability. Among the various existing solid supports and immobilization strategies, the in situ encapsulation of enzymes within crystalline porous matrices is a powerful tool to design biohybrids with a stable and protected catalytic activity. However, to date, only a few metal–organic frameworks (MOFs) and hydrogen-bonded organic frameworks (HOFs) have been reported. Excitingly, for the first time, Y. Chen and co-workers expanded the in situ bioencapsulation to a new class of crystalline porous materials, namely covalent organic frameworks (COFs). The enzyme@COF materials not only exhibited high enzyme loading with minimal leaching, high catalytic activity and selectivity, chemical and long-term stability and recyclability but could also be scaled up to a few grams. Undoubtedly, this work opens new striking opportunities for enzymatic immobilization and will stimulate new research on COF-based matrices.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Clémence Sicard
onlinelibrary.wiley.com/doi/10.1002/anie.202213405

An Analytical Specialty Team Enabling Merck’s Pipeline with Pioneering Measurement Science

An Analytical Specialty Team Enabling Merck's Pipeline with Pioneering Measurement Science

“A cross-disciplinary collaboration between the pharmaceutical industry and academia enables modern (bio)pharmaceutical processes… Avoiding the unexpected or running away from difficult pipeline requests is not a choice.„ Find out more about the cross-discipline collaboration of Erik Regalado and his co-workers.”

Abstract

This invited Team Profile was created by the above group. They recently published an article on the introduction of a hybrid separation technique, referred to as Dual-Gradient Unified Chromatography (DGUC), enabling simultaneous multicomponent analysis of both small and large molecules across a wide polarity range in single experimental runs. DGUC lays the foundation for the next generation of hybrid chromatographic techniques with the deployment of universal elution profiles obtained via multi-eluent blending beyond traditional separation modes. “Dual-Gradient Unified Chromatography: A New Paradigm for Versatility in Simultaneous Multicomponent Analysis”, G. L. Losacco, R. Bennett, I. A. Haidar Ahmad, R. C. Barrientos, J. O. DaSilva, Y. Dong, A. W. Schuppe, Z. Wang, S. Aiken, I. Mangion, V. K. Aggarwal, E. L. Regalado, Angew. Chem. Int. Ed. 2022, e202208854; Angew. Chem. 2022, e202208854.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors:
onlinelibrary.wiley.com/doi/10.1002/anie.202214918

A General Method to Edit Histone H3 Modifications on Chromatin Via Sortase‐Mediated Metathesis

A General Method to Edit Histone H3 Modifications on Chromatin Via Sortase-Mediated Metathesis

A sortase-based method of histone H3 tail editing on chromatin is reported. Histone H3 tail peptides with cell-penetrating sequence can be metathesized to histone H3 for multivalent modifications on chromatin and influence epigenetics. This described sortase mediated metathesis strategy could be broadly applied to edit endogenous proteins in live cells.

Abstract

The post-translational modifications (PTMs) on the tail of histone H3 control chromatin structure and influence epigenetics and gene expression. The current chemical methods including unnatural amino acid incorporation and protein splicing enable preparations of the histone with diverse PTMs in cellular contexts, but they are not applicable to edit native chromatin. The manipulation of histone-modifying enzymes alter the endogenous histone PTMs but the lack of specificity of most histone-modifying enzymes prevents precise control of specific H3 tail PTM patterns. Here we report a new method to edit the N-tail of histone H3 via sortase mediated metathesis (SMM). The sortase can install desired PTM patterns into histone H3 on nucleosomes in vitro and in cellulo. This study expands the application scope of sortase from ligation to metathesis in live cells using cell-penetrating peptides (CPPs). In addition, it offers a strategy to edit PTMs of cellular histone H3 with potential for the development of precise epigenome editing.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Qingyun Yang, Yingxiao Gao, Xia Liu, Yihang Xiao, Mingxuan Wu
onlinelibrary.wiley.com/doi/10.1002/anie.202209945

The Electronic Origin of the Zeta Potential is Supported by the Redox Mechanism on an Aqueous Dispersion of Exfoliated Graphite

The Electronic Origin of the Zeta Potential is Supported by the Redox Mechanism on an Aqueous Dispersion of Exfoliated Graphite

An aqueous graphite dispersion was prepared without passivating agents and a minimal amount of functional groups by treating graphite with ammonium hydroxide. This approach has raised the Fermi level above the original value. The negative zeta potential has been revisited and attributed to the electrons accumulated on the material.

Abstract

Herein we have proposed that a redox mechanism can produce surface charges and negative zeta potential on an aqueous graphite dispersion. Graphite was kept in contact with a concentrated ammonia aqueous solution, washed, and exfoliated in water, resulting in a dispersion with lyophobic nature. Ammonia treatment did not provide functional groups or nitrogen doping to graphite. Moreover, this material was washed twice before sonication to remove most hydroxide. Therefore, neither functional groups, nitrogen atoms, nor hydroxide excess is responsible for the zeta potential. Kelvin probe force microscopy has shown that the ammonia-treated and exfoliated graphite has higher Fermi level than the water-treated material, indicating that the contact between ammonia and graphite promotes redox reactions that provide electrons to graphite. These electrons raise the Fermi level of graphite and generate the negative zeta potential, consequently, they account for the colloidal stability.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: João Paulo Vita Damasceno, Lauro Tatsuo Kubota
onlinelibrary.wiley.com/doi/10.1002/anie.202214995

Multi‐Spatiotemporal Probing of Neurochemical Events by Advanced Electrochemical Sensing Methods

Multi-Spatiotemporal Probing of Neurochemical Events by Advanced Electrochemical Sensing Methods

Advanced electrochemical sensing has greatly increased the amount of information available on neurochemical events at all spatiotemporal dimensionalities. This Minireview highlights the latest progress on the individualized electrochemical description of vesicle properties and chemical content, single-cell monitoring of transient exocytotic release, in vivo selective amperometric sensing of neurochemical dynamics, and concurrent recording of multiple brain signals.

Abstract

Neurochemical events involving biosignals of different time and space dimensionalities constitute the complex basis of neurological functions and diseases. In view of this fact, electrochemical measurements enabling real-time quantification of neurochemicals at multiple levels of spatiotemporal resolution can provide informative clues to decode the molecular networks bridging vesicles and brains. This Minireview focuses on how scientific questions regarding the properties of single vesicles, neurotransmitter release kinetics, interstitial neurochemical dynamics, and multisignal interconnections in vivo have driven the design of electrochemical nano/microsensors, sensing interface engineering, and signal/data processing. An outlook for the future frontline in this realm will also be provided.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Fei Wu, Ping Yu, Lanqun Mao
onlinelibrary.wiley.com/doi/10.1002/anie.202208872

One‐Shot Synthesis of B/N‐Doped Calix[4]arene Exhibiting Narrowband Multiple Resonance Fluorescence

One-Shot Synthesis of B/N-Doped Calix[4]arene Exhibiting Narrowband Multiple Resonance Fluorescence

A novel boron- and nitrogen-doped calix[4]arene named C-BN was successfully synthesized through one-shot double borylation. C-BN shows a highly centrosymmetric structure with two multiple resonance fragments bridged by tertiary amine groups at the 1,3 positions of the benzene ring. The optimized organic light-emitting diodes can exhibit high maximum external quantum efficiencies of 24.7–26.6 % and small full-width-at-half-max of 25–28 nm over a wide doping range of 1–12 wt %.

Abstract

A novel macrocycle of B/N-doped calix[4]arene (C-BN) was synthesized by a one-shot double boronation. Owing to the structural tension and electron-donating properties of the nitrogen atoms in the macrocycle, reaction selectively proceeds between the adjacent benzene rings outside the macrocycle. C-BN shows a highly centrosymmetric structure with two multiple resonance (MR) fragments bridged by tertiary amine groups at the 1,3 positions of the benzene ring. Benefiting from the large intermolecular distance (>4.6 Å) between adjacent MR-emitting cores, C-BN also exhibits excellent narrowband emitting features against aggregation-induced quenching and spectrum broadening. Optimized organic light-emitting diode devices based on C-BN exhibit high maximum external quantum efficiencies of 24.7–26.6 % and small full width at half maximums of 25–28 nm over a wide doping range of 1–12 wt %.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Tianjiao Fan, Yuewei Zhang, Lu Wang, Qian Wang, Chen Yin, Mingxu Du, Xiaoqin Jia, Guomeng Li, Lian Duan
onlinelibrary.wiley.com/doi/10.1002/anie.202213585

Self‐assembled Ru(bda) Coordination Oligomers as Efficient Catalysts for Visible Light‐Driven Water Oxidation in Pure Water

Self-assembled Ru(bda) Coordination Oligomers as Efficient Catalysts for Visible Light-Driven Water Oxidation in Pure Water

Water-soluble Ru(bda) coordination oligomers with varying lengths are investigated in visible light-driven water oxidation catalysis. The excellent performance and stability of longer oligomers in pure water is rationalized by the very high local concentrations of active sites in self-assembled superstructures.

Abstract

Water-soluble multinuclear complexes based on ruthenium 2,2′-bipyridine-6,6′-dicarboxylate (bda) and ditopic bipyridine linker units are investigated in three-component visible light-driven water oxidation catalysis. Systematic studies revealed a strong enhancement of the catalytic efficiency in the absence of organic co-solvents and with increasing oligomer length. In-depth kinetic and morphological investigations suggest that the enhanced performance is induced by the self-assembly of linear Ru(bda) oligomers into aggregated superstructures. The obtained turnover frequencies (up to 14.9 s−1) and turnover numbers (more than 1000) per ruthenium center are the highest reported so far for Ru(bda)-based photocatalytic water oxidation systems.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Tim Schlossarek, Vladimir Stepanenko, Florian Beuerle, Frank Würthner
onlinelibrary.wiley.com/doi/10.1002/anie.202211445

Atroposelective Synthesis of Triaryl α‐Pyranones with 1,2‐Diaxes by N‐Heterocyclic Carbene Organocatalysis

Atroposelective Synthesis of Triaryl α-Pyranones with 1,2-Diaxes by N-Heterocyclic Carbene Organocatalysis

The single-step atroposelective construction of stereogenic 1,2-diaxes of triaryl α-pyranones was accomplished by NHC organocatalysis. The structure of the substrates and the catalytic system play a critical role in the success of this protocol. DFT calculations were performed to rationalize the origin of the high stereoselectivity.

Abstract

Atropisomers bearing multiple stereogenic axes are of increasing importance to the field of material science, pharmaceuticals, and catalysis. However, the atroposelective construction of multi-axis atropisomers remains rare and challenging, due to the intrinsical difficulties in the stereo-control of the multiple stereogenic axes. Herein, we demonstrate a single-step construction of a new class of 1,2-diaxially chiral triaryl α-pyranones by an N-heterocyclic carbene organocatalytic asymmetric [3+3] annulation of well-designed alkynyl acylazolium precursors and enolizable sterically hindered 2-aryl ketones. The protocol features broad substrate scope (>50 examples), excellent stereo-control (most cases >20 : 1 dr, up to 99.5 : 0.5 er), and potentially useful synthetic applications. The success of this reaction relies on the rational design of structurally matched reaction partners and the careful selection of the asymmetric catalytic system. DFT calculations have also been performed to discover and rationalize the origin of the high stereoselectivity of this reaction.

Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Simiao Zhang, Xiaoxue Wang, Li‐Li Han, Jibin Li, Zheng Liang, Donghui Wei, Ding Du
onlinelibrary.wiley.com/doi/10.1002/anie.202212005