bluuebunny/crossref_metadata_2025 huggingface dataset:
BiPO4‐Derived 2D Nanosheets for Efficient Electrocatalytic Reduction of CO2 to Liquid Fuel
Authors: Wang Yating , Li Yuhang , Liu Jinze , Dong Chunxiao , Xiao Chuqian , Cheng Ling , Jiang Hongliang , Jiang Hao , Li Chunzhong
Published: January 2021

The electrochemical reduction of carbon dioxide (CO2) to high‐value liquid fuel with high selectivity is appealing for energy conversion and storage. Here we report a bismuth phosphate (BiPO4) derived 2D nanosheet‐like electrocatalyst that efficiently converts CO2 into liquid‐phase formate. The catalyst presents a formate Faradaic efficiency of over 90 % and a cathodic energy efficiency of 73 % at an industrially relevant current density of 200 mA cm−2 in the flow cell. The in situ generation of the Bi‐O active species on the catalyst surface was determined via operando Raman measurement. Morphological and X‐ray photoelectron spectroscopy analyses reveal the origin of the high activity for the electrosynthesis of formate from CO2 and water: the 2D structure together with the abundant insertion of oxygen atoms in the surface of the BiPO4‐derived nanosheets.
In Vivo Assembly of Artificial Metalloenzymes and Application in Whole‐Cell Biocatalysis**
Authors: Chordia Shreyans , Narasimhan Siddarth , Lucini Paioni Alessandra , Baldus Marc , Roelfes Gerard
Published: January 2021

We report the supramolecular assembly of artificial metalloenzymes (ArMs), based on the Lactococcal multidrug resistance regulator (LmrR) and an exogeneous copper(II)–phenanthroline complex, in the cytoplasm of E. coli cells. A combination of catalysis, cell‐fractionation, and inhibitor experiments, supplemented with in‐cell solid‐state NMR spectroscopy, confirmed the in‐cell assembly. The ArM‐containing whole cells were active in the catalysis of the enantioselective Friedel–Crafts alkylation of indoles and the Diels–Alder reaction of azachalcone with cyclopentadiene. Directed evolution resulted in two different improved mutants for both reactions, LmrR_A92E_M8D and LmrR_A92E_V15A, respectively. The whole‐cell ArM system required no engineering of the microbial host, the protein scaffold, or the cofactor to achieve ArM assembly and catalysis. We consider this a key step towards integrating abiological catalysis with biosynthesis to generate a hybrid metabolism.
Effect of Metal–Organic Framework (MOF) Database Selection on the Assessment of Gas Storage and Separation Potentials of MOFs
Authors: Daglar Hilal , Gulbalkan Hasan Can , Avci Gokay , Aksu Gokhan Onder , Altundal Omer Faruk , Altintas Cigdem , Erucar Ilknur , Keskin Seda
Published: January 2021

Development of computation‐ready metal–organic framework databases (MOF DBs) has accelerated high‐throughput computational screening (HTCS) of materials to identify the best candidates for gas storage and separation. These DBs were constructed using structural curations to make MOFs directly usable for molecular simulations, which caused the same MOF to be reported with different structural features in different DBs. We examined thousands of common materials of the two recently updated, very widely used MOF DBs to reveal how structural discrepancies affect simulated CH4, H2, CO2 uptakes and CH4/H2 separation performances of MOFs. Results showed that DB selection has a significant effect on the calculated gas uptakes and ideal selectivities of materials at low pressure. A detailed analysis on the curated structures was provided to isolate the critical elements of MOFs determining the gas uptakes. Identification of the top‐performing materials for gas separation was shown to strongly depend on the DB used in simulations.
On‐Surface Hydrogen/Deuterium Isotope Exchange in Polycyclic Aromatic Hydrocarbons
Authors: Wäckerlin Christian
Published: January 2021

Hydrogen plays important roles in the on‐surface synthesis of carbon‐based materials in ultra‐high vacuum. The complex interplay between hydrogen and surface‐adsorbed polycyclic aromatic hydrocarbons (PAHs) is tracked by in situ time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) combined with isotope labeling. In situ deuterium labeling of prototypical PAHs, coronene (CR) and 7‐armchair graphene nanoribbons (GNRs), on Au(111) is achieved by annealing either in D2 gas or in the vapor of perdeuterio‐acenaphthene. By following the mass spectra of in situ deuterated CR mixed with hydrogen‐CR, it is demonstrated that PAHs adsorbed at hot Au(111) surfaces continuously exchange hydrogen atoms. Also, D2 present during the Ullmann coupling step leads to incorporation of deuterium and to shorter GNRs.
In‐vitro and In‐vivo Photocatalytic Cancer Therapy with Biocompatible Iridium(III) Photocatalysts
Authors: Huang Can , Liang Chao , Sadhukhan Tumpa , Banerjee Samya , Fan Zhongxian , Li Tingxuan , Zhu Zilin , Zhang Pingyu , Raghavachari Krishnan , Huang Huaiyi
Published: January 2021

Photocatalytic anticancer profile of a IrIIIphotocatalyst (Ir3) with strong light absorption, high turnover frequency, and excellent biocompatibility is reported.Ir3showed selective photo‐cytotoxicity against cisplatin‐ and sorafenib‐resistant cell lines while remaining dormant to normal cell lines in the dark.Ir3exhibited excellent photo‐catalytic oxidation of cellular co‐enzyme, the reduced nicotinamide adenine dinucleotide phosphate (NADPH), and amino acids via a single electron transfer mechanism. The photo‐induced intracellular redox imbalance and change in mitochondrial membrane potential resulted in necrosis and apoptosis of cancer cells. Importantly,Ir3exhibited high biocompatibility and photo‐catalytic anticancer efficiency as evident from in vivo zebrafish and mouse cancer models. To the best of our knowledge,Ir3is the first IrIIIbased photocatalyst with such a high biocompatibility and photocatalytic anticancer therapeutic effect.
Robust Packing of a Self‐Assembling Iridium Complex via Endocytic Trafficking for Long‐Term Lysosome Tracking
Authors: Jin Chengzhi , Li Guanying , Wu Xia , Liu Jiangping , Wu Weijun , Chen Yazhou , Sasaki Toshio , Chao Hui , Zhang Ye
Published: January 2021

Live cell imaging of lysosome positioning and motility is critical to studying lysosome status and function for pharmacological interventions. To create a super stable lysosomal probe for long‐term live cell imaging, we have designed and synthesized an aromatic‐peptide‐conjugated cyclometalated iridium(III) complex that emits light via π–π stacking oriented self‐assembly in water at extremely low concentration. Through endocytic trafficking, self‐assemblies are transformed from nanoparticles into sturdily packed networks that are stabilized in lysosomal acidic environment. Upon short time/low dose treatment of the iridium complex at passage 0, live cell lysosomal tracking is applicable beyond the 14th passage of cells with high labelling rate and a mild decline in luminescence intensity. The illuminated lysosomes are trackable using super‐resolution imaging to study their response to cellular processes.
Eine chirale pentafluorierte Isopropylgruppe durch Iod(I)/(III)‐Katalyse
Authors: Meyer Stephanie , Häfliger Joel , Schäfer Michael , Molloy John J. , Daniliuc Constantin G. , Gilmour Ryan
Published: January 2021

Eine durch Iod (I/III) Katalyse ermöglichte Strategie zur Konstruktion eines enantioangereicherten fluorierten Isoster der Isopropylgruppe wird beschrieben. Die in situ Generierung einer chiralen ArIF2‐Spezies ermöglicht die Difluorierung von leicht zugänglichen α‐CF3‐Styrolen, um ein Stereozentrum mit den Substituenten F, CH2F und CF3 aufzubauen (bis zu 95 %, >20:1 vicinale:geminale Difluorierung). Der Austausch des metabolisch labilen benzylischen Protons führt zu einem stark präorganisierten Gerüst, welches durch Röntgenstrukturanalyse nachgewiesen werden konnte (π→σ* und stereoelektronische gauche σ→σ* Wechselwirkungen). Um die Basis für die vorläufige Validierung der Enantioselektivität zu bilden, wurde eine Katalysatoroptimierung durchgeführt.
Advanced Real‐Time Process Analytics for Multistep Synthesis in Continuous Flow**
Authors: Sagmeister Peter , Lebl René , Castillo Ismael , Rehrl Jakob , Kruisz Julia , Sipek Martin , Horn Martin , Sacher Stephan , Cantillo David , Williams Jason D. , Kappe C. Oliver
Published: January 2021

In multistep continuous flow chemistry, studying complex reaction mixtures in real time is a significant challenge, but provides an opportunity to enhance reaction understanding and control. We report the integration of four complementary process analytical technology tools (NMR, UV/Vis, IR and UHPLC) in the multistep synthesis of an active pharmaceutical ingredient, mesalazine. This synthetic route exploits flow processing for nitration, high temperature hydrolysis and hydrogenation reactions, as well as three inline separations. Advanced data analysis models were developed (indirect hard modeling, deep learning and partial least squares regression), to quantify the desired products, intermediates and impurities in real time, at multiple points along the synthetic pathway. The capabilities of the system have been demonstrated by operating both steady state and dynamic experiments and represents a significant step forward in data‐driven continuous flow synthesis.
Rigid Polyimides with Thermally Activated Delayed Fluorescence for Polymer Light‐Emitting Diodes with High External Quantum Efficiency up to 21 %
Authors: Long Yubo , Chen Xiaojie , Wu Huiyan , Zhou Zhuxin , Sriram Babu Seenivasagaperumal , Wu Minming , Zhao Juan , Aldred Matthew P. , Liu Siwei , Chen Xudong , Chi Zhenguo , Xu Jiarui , Zhang Yi
Published: January 2021

A series of rigid nonconjugated polyimide (PI)‐based thermally activated delayed fluorescence (TADF) polymers were reported for the first time, based on a “TADF‐Linker‐Host” strategy. Among of which, the TADF unit contains a typical TADF luminous core structure, the “Host” unit exhibits effective conjugation length that endows polyimide with high triplet energy, and the “Linker” unit has an aliphatic ring structure to improve solubility and inhibits intramolecular charge transfer effect. All the TADF polymers exhibit high thermal stability (Tg>308.7 °C) and refractive index (1.76–1.79). Remarkably, highly‐efficient polymer light‐emitting diodes (PLEDs) based on the polymers are successfully realized, leading to a maximal external quantum efficiency of 21.0 % along with low efficiency roll‐off. Such outstanding efficiency is amongst the state‐of‐the‐art performance of nonconjugated PLEDs, confirming the effectiveness of structural design strategy, providing helpful and valuable guidance on the development of highly‐efficient fluorescent polymer materials and PLEDs.
Exclusive Strain Effect Boosts Overall Water Splitting in PdCu/Ir Core/Shell Nanocrystals
Authors: Li Menggang , Zhao Zhonglong , Xia Zhonghong , Luo Mingchuan , Zhang Qinghua , Qin Yingnan , Tao Lu , Yin Kun , Chao Yuguang , Gu Lin , Yang Weiwei , Yu Yongsheng , Lu Gang , Guo Shaojun
Published: January 2021

Core/shell nanocatalysts are a class of promising materials, which achieve the enhanced catalytic activities through the synergy between ligand effect and strain effect. However, it has been challenging to disentangle the contributions from the two effects, which hinders the rational design of superior core/shell nanocatalysts. Herein, we report precise synthesis of PdCu/Ir core/shell nanocrystals, which can significantly boost oxygen evolution reaction (OER) via the exclusive strain effect. The heteroepitaxial coating of four Ir atomic layers onto PdCu nanoparticle gives a relatively thick Ir shell eliminating the ligand effect, but creates a compressive strain of ca. 3.60%. The strained PdCu/Ir catalysts can deliver a low OER overpotential and a high mass activity. Density functional theory (DFT) calculations reveal that the compressive strain in Ir shell downshifts the d‐band center and weakens the binding of the intermediates, causing the enhanced OER activity. The compressive strain also boosts hydrogen evolution reaction (HER) activity and the strained nanocrystals can be served as excellent catalysts for both anode and cathode in overall water‐splitting electrocatalysis.
Assembly of Dynamic Supramolecular Polymers on a DNA Origami Platform
Authors: Schill Jurgen , Rosier Bas J. H. M. , Gumí Audenis Berta , Magdalena Estirado Eva , de Greef Tom F. A. , Brunsveld Luc
Published: January 2021

Biological processes rely on transient interactions that govern assembly of biomolecules into higher order, multi‐component systems. A synthetic platform for the dynamic assembly of multicomponent complexes would provide novel entries to study and modulate the assembly of artificial systems into higher order topologies. Here, we establish a hybrid DNA origami‐based approach as an assembly platform that enables dynamic templating of supramolecular architectures. It entails the site‐selective recruitment of supramolecular polymers to the platform with preservation of the intrinsic dynamics and reversibility of the assembly process. The composition of the supramolecular assembly on the platform can be tuned dynamically, allowing for monomer rearrangement and inclusion of molecular cargo. This work should aid the study of supramolecular structures in their native environment in real‐time and incites new strategies for controlled multicomponent self‐assembly of synthetic building blocks.
Stanene‐Based Nanosheets for β‐Elemene Delivery and Ultrasound‐Mediated Combination Cancer Therapy
Authors: Chen Wei , Liu Chuang , Ji Xiaoyuan , Joseph John , Tang Zhongmin , Ouyang Jiang , Xiao Yufen , Kong Na , Joshi Nitin , Farokhzad Omid C. , Tao Wei , Xie Tian
Published: January 2021

Ultrasound (US)‐mediated sonodynamic therapy (SDT) has emerged as a superior modality for cancer treatment owing to the non‐invasiveness and high tissue‐penetrating depth. However, developing biocompatible nanomaterial‐based sonosensitizers with efficient SDT capability remains challenging. Here, we employed a liquid‐phase exfoliation strategy to obtain a new type of two‐dimensional (2D) stanene‐based nanosheets (SnNSs) with a band gap of 2.3 eV, which is narrower than those of the most extensively studied nano‐sonosensitizers, allowing a more efficient US‐triggered separation of electron (e−)‐hole (h+) pairs for reactive oxygen species (ROS) generation. In addition, we discovered that such SnNSs could also serve as robust near‐infrared (NIR)‐mediated photothermal therapy (PTT) agents owing to their efficient photothermal conversion, and serve as nanocarriers for anticancer drug delivery owing to the inherent 2D layered structure. This study not only presents general nanoplatforms for SDT‐enhanced combination cancer therapy, but also highlights the utility of 2D SnNSs to the field of nanomedicine.
Silver‐Catalyzed Enantioselective Sulfimidation Mediated by Hydrogen Bonding Interactions
Authors: Annapureddy Rajasekar Reddy , Burg Finn , Gramüller Johannes , Golub Tino P. , Merten Christian , Huber Stefan M. , Bach Thorsten
Published: January 2021

An enantioselective sulfimidation of 3‐thiosubstituted 2‐quinolones and 2‐pyridones was achieved with a stoichiometric nitrene source (PhI=NNs) and a silver‐based catalyst system. Key to the success of the reaction is the use of a chiral phenanthroline ligand with a hydrogen bonding site. The enantioselectivity does not depend on the size of the two substituents at the sulfur atom but only on the binding properties of the heterocyclic lactams. A total of 21 chiral sulfimides were obtained in high yields (44–99 %) and with significant enantiomeric excess (70–99 % ee). The sulfimidation proceeds with high site‐selectivity and can also be employed for the kinetic resolution of chiral sulfoxides. Mechanistic evidence suggests the intermediacy of a heteroleptic silver complex, in which the silver atom is bound to one molecule of the chiral ligand and one molecule of an achiral 1,10‐phenanthroline. Support for the suggested reaction course was obtained by ESI mass spectrometry, DFT calculations, and a Hammett analysis.
Protic Ionic Liquid as Reagent, Catalyst, and Solvent: 1‐Methylimidazolium Thiocyanate
Authors: Andreev Ivan A. , Ratmanova Nina K. , Augustin André U. , Ivanova Olga A. , Levina Irina I. , Khrustalev Victor N. , Werz Daniel B. , Trushkov Igor V.
Published: January 2021

We propose a new concept of the triple role of protic ionic liquids with nucleophilic anions: a) a regenerable solvent, b) a Brønsted acid inducing diverse transformations via general acid catalysis, and c) a source of a nucleophile. The efficiency of this strategy was demonstrated using thiocyanate‐based protic ionic liquids for the ring‐opening of donor‐acceptor cyclopropanes. A wide variety of activated cyclopropanes were found to react with 1‐methylimidazolium thiocyanate under mild metal‐free conditions via unusual nitrogen attack of the ambident thiocyanate ion on the electrophilic center of the three‐membered ring affording pyrrolidine‐2‐thiones bearing donor and acceptor substituents at the C(5) and C(3) atoms, respectively, in a single time‐efficient step. The ability of 1‐methylimidazolium thiocyanate to serve as a triplex reagent was exemplarily illustrated by (4+2)‐annulation with 1‐acyl‐2‐(2‐hydroxyphenyl)cyclopropane, epoxide ring‐opening and other organic transformations.
Ligand‐Directed Approach in Polyoxometalate Synthesis: Formation of a New Divacant Lacunary Polyoxomolybdate [γ‐PMo10O36]7−
Authors: Li Chifeng , Yamaguchi Kazuya , Suzuki Kosuke
Published: January 2021

Polyoxometalates (POMs) have received increasing attention over the last decades for extending their application and properties that originate from novel structures. For the synthesis of a variety of POM structures, multivacant lacunary POMs are key precursors, which are typically synthesized by empirically controlling the complex equilibrium in aqueous solvents. Unfortunately, despite the excellent catalytic and electrochemical properties of “polyoxomolybdates”, only one multivacant lacunary species, i.e., [A‐α‐PMo9O34]9−, has been identified and isolated because multivacant lacunary polyoxomolybdates are typically unstable. Here we report a ligand‐directed approach for the selective formation of an unprecedented lacunary polyoxomolybdate in organic solvents. By structure transformation of a pyridine‐coordinated [A‐α‐PMo9O34]9−, a new γ‐Keggin‐type divacant lacunary polyoxomolybdate [γ‐PMo10O36]7− was obtained, which can be further used as a precursor for synthesizing a POM–organic hybrid.
Die entscheidende Rolle von lokalen Ladungsfluktuationen beim Wachstum von Dendriten auf Lithium‐Elektroden
Authors: Santos Elizabeth , Schmickler Wolfgang
Published: January 2021

Obwohl sich sehr viele theoretische Arbeiten mit der Ursache der Dendritenbildung an reinen Lithium‐Elektroden befasst haben, wurde bisher ein entscheidender Faktor übersehen: Bei der Abscheidung von Lithium ist die Elektrode stark negativ geladen, und diese Ladung ist nicht gleichmäßig über die Oberfläche verteilt. Explizite Modellrechnungen zeigen, dass sich die Überschussladung auf der Spitze kleiner Unebenheiten, die durch Fluktuationen entstehen, konzentriert. Sie erzeugt dort ein starkes elektrisches Feld, welches Lithium‐Ionen anzieht, die Spitze weiter wachsen lässt und schließlich zur Bildung von Dendriten führt. Selbst eine kleine Spitze, die nur aus wenigen Atomen besteht, trägt eine Überschussladung von der Größenordnung eines Zehntels der Elektronenladung oder mehr. Zudem erniedrigt eine negative Ladung lokal die Oberflächenspannung, was die Dendritenbildung zusätzlich begünstigt. Derselbe Mechanismus kann auch die Dendritenbildung an anderen Metallen erklären, deren Abscheidungspotential tiefer liegt als der Ladungsnullpunkt.
Electrochemical Splitting of Methane in Molten Salts To Produce Hydrogen
Authors: Fan Zeyu , Xiao Wei
Published: January 2021

Industrial hydrogen production based on methane steam reforming (MSR) remains challenges in intensive carbon emissions, retarded hydrogen generation owing to coke deposition over catalysts and huge consumption of water. We herein report an electrochemical splitting of methane (ESM) in molten salts at 500 °C to produce hydrogen in an energy saving, emission‐free and water‐free manner. Following the most energy‐saving route on methane‐to‐hydrogen conversion, methane is electrochemically oxidized at anode to generate carbon dioxide and hydrogen. The generated anodic carbon dioxide is in situ captured by the melts and reduced to solid carbon at cathode, enabling a spatial separation of anodic hydrogen generation from cathodic carbon deposition. Life‐cycle assessment on hydrogen‐generation technologies shows that the ESM experiences an equivalent carbon emission much lower than MSR, and a lower equivalent energy input than alkaline water electrolysis.
A Fast Room‐Temperature Self‐Healing Glassy Polyurethane
Authors: Xu JianHua , Chen JiaoYang , Zhang YaNa , Liu Tong , Fu JiaJun
Published: January 2021

We designed and synthesized a colorless transparent glassy polyurethane assembled using low‐molecular‐weight oligomers carrying a large number of loosely packed weak hydrogen bonds (H‐bonds), which has a glass transition temperature (Tg) up to 36.8 °C and behaves unprecedentedly robust stiffness with a tensile Young's modulus of 1.56±0.03 GPa. Fast room‐temperature self‐healing was observed in this polymer network: the broken glassy polyurethane (GPU) specimen can recover to a tensile strength up 7.74±0.76 MPa after healing for as little as 10 min, which is prominent compared to reported room‐temperature self‐healing polymers. The high density of loose‐packed hydrogen bonds can reversibly dissociate/associate below Tg of GPU (that is secondary relaxation), which enables the reconfiguration of the damaged network in the fractured interfaces, despite the extremely slow diffusion dynamics of molecular chains under room temperature. This GPU shows potential application as an optical lens.
Enzyme‐Loaded Nanoreactors Enable the Continuous Regeneration of Nicotinamide Adenine Dinucleotide in Artificial Metabolisms
Authors: Jo Seong‐Min , Wurm Frederik R. , Landfester Katharina
Published: January 2021

Nicotinamide adenine dinucleotide (NAD) is an essential coenzyme for numerous biocatalytic pathways. While in nature, NAD+ is continuously regenerated from NADH by enzymes, all synthetic NAD+ regeneration strategies require a continuous supply of expensive reagents and generate byproducts, making these strategies unattractive. In contrast, we present an artificial enzyme combination that produces NAD+ from oxygen and water continuously; no additional organic substrates are required once a minimal amount pyruvate is supplied. Three enzymes, i.e., LDH, LOX, and CAT, are covalently encapsulated into a substrate‐permeable silica nanoreactor by a mild fluoride‐catalyzed sol–gel process. The enzymes retain their activity inside of the nanoreactors and are protected against proteolysis and heat. We successfully used NAD+ from the nanoreactors for the continuous production of NAD+ i) to sense glucose in artificial glucose metabolism, and ii) to reduce the non‐oxygen binding methemoglobin to oxygen‐binding hemoglobin. This latter conversion might be used for the treatment of Methemoglobinemia. We believe that this versatile tool will allow the design of artificial NAD+‐dependent metabolisms or NAD+‐mediated redox‐reactions.
Synthesis of Core@Shell Cu‐Ni@Pt‐Cu Nano‐Octahedra and Their Improved MOR Activity
Authors: Li Can , Chen Xiaobo , Zhang Lihua , Yan Shaohui , Sharma Anju , Zhao Bo , Kumbhar Amar , Zhou Guangwen , Fang Jiye
Published: January 2021

Fabrication of 3d metal‐based core@shell nanocatalysts with engineered Pt‐surfaces provides an effective approach for improving the catalytic performance. The challenges in such preparation include shape control of the 3d metallic cores and thickness control of the Pt‐based shells. Herein, we report a colloidal seed‐mediated method to prepare octahedral CuNi@Pt‐Cu core@shell nanocrystals using CuNi octahedral cores as the template. By precisely controlling the synthesis conditions including the deposition rate and diffusion rate of the shell‐formation through tuning the capping ligand, reaction temperature, and heating rate, uniform Pt‐based shells can be achieved with a thickness of <1 nm. The resultant carbon‐supported CuNi@Pt‐Cu core@shell nano‐octahedra showed superior activity in electrochemical methanol oxidation reaction (MOR) compared with the commercial Pt/C catalysts and carbon‐supported CuNi@Pt‐Cu nano‐polyhedron counterparts.
Biodegradable Charge‐Transfer Complexes for Glutathione Depletion Induced Ferroptosis and NIR‐II Photoacoustic Imaging Guided Cancer Photothermal Therapy
Authors: Ou Changjin , Na Weidan , Ge Wei , Huang Han , Gao Fan , Zhong Liping , Zhao Yongxiang , Dong Xiaochen
Published: January 2021

Suffering from the laborious synthesis and undesirable tumor microenvironment response, the exploitation of novel NIR‐II absorbing organic photothermal agents is of importance to promote phototherapeutic efficacy. Herein, two kinds of charge‐transfer complex nanoparticles (TMB‐F4TCNQ and TMB‐TCNQ) are prepared by supramolecular assembly. Because of the larger energy gap between donor and acceptor, TMB‐F4TCNQ presents higher charge‐transfer degree (72 %) than that of TMB‐TCNQ (48 %) in nanoaggregates. Therefore, TMB‐F4TCNQ exhibits stronger NIR‐II absorption ability with a mass extinction coefficient of 15.4 Lg−1 cm−1 at 1300 nm and excellent photothermal effect. Impressively, the specific cysteine response can make the TMB‐F4TCNQ effectively inhibit the intracellular biosynthesis of GSH, leading to redox dsyhomeostasis and ROS‐mediated ferroptosis. TMB‐F4TCNQ can serve as a contrast agent for NIR‐II photoacoustic imaging to guide precise and efficient photothermal therapy in vivo.
Controllable Self‐Assembly of Peptide‐Cyanine Conjugates In Vivo as Fine‐Tunable Theranostics
Authors: Zheng Rui , Yang Jia , Mamuti Muhetaerjiang , Hou Da‐Yong , An Hong‐Wei , Zhao Yuliang , Wang Hao
Published: January 2021

The fabrication of functional assemblies with defined structures through controllable molecular packing under physiological conditions is challenging. Here, modularly designed peptide‐cyanine conjugates that intracellularly self‐assembly into 1D columnar superstructures with controlled cyanine aggregation were designed, and they exhibit distinct imaging or photothermal properties. The peptide backbone is cleaved by caspase‐3/7 after entering the cells. Then the self‐assembled residue, with a double cyanine substitution (Pr‐2Cy), forms a P helical column in which H‐aggregated cyanine dyes show 3.4‐fold photothermal conversion efficiency compared to free ones. The self‐assembled residue with a single cyanine substitution (Pr‐1Cy) forms a loose column, in which cyanine dyes with undefined structure have a fluorescence quantum yield of up to 9.5 % (emission at 819 nm in H2O). This work provides a simple way to modify in vivo self‐assembled peptides with functional molecules for achieving desired bio‐applications.
Coupling of Reformatsky Reagents with Aryl Chlorides Enabled by Ylide‐Functionalized Phosphine Ligands
Authors: Hu Zhiyong , Wei Xiao‐Jing , Handelmann Jens , Seitz Ann‐Katrin , Rodstein Ilja , Gessner Viktoria H. , Gooßen Lukas J.
Published: January 2021

The coupling of aryl chlorides with Reformatsky reagents is a desirable strategy for the construction of α‐aryl esters but has so far been substantially limited in the substrate scope due to many challenges posed by various possible side reactions. This limitation has now been overcome by the tailoring of ylide‐functionalized phosphines to fit the requirements of Negishi couplings. Record‐setting activities were achieved in palladium‐catalyzed arylations of organozinc reagents with aryl electrophiles using a cyclohexyl‐YPhos ligand bearing an ortho‐tolyl‐substituent in the backbone. This highly electron‐rich, bulky ligand enables the use of aryl chlorides in room temperature couplings of Reformatsky reagents. The reaction scope covers diversely functionalized arylacetic and arylpropionic acid derivatives. Aryl bromides and chlorides can be converted selectively over triflate electrophiles, which permits consecutive coupling strategies.
Generation of Elemental Fluorine through the Electrolysis of Copper Difluoride at Room Temperature
Authors: Matsumoto Kazuhiko , Shima Keita , Sugimoto Takuya , Inoue Takahiro , Hagiwara Rika
Published: January 2021

The safe generation of F2gas at room temperature by using simple cell configurations has been the “holy grail” of fluorine research for centuries. Thus, to address this issue, we report generation of F2gas through the electrolysis of CuF2in a CsF‐2.45HF molten salt without the evolution of H2gas. The CuF2is selected through a series of thermodynamic and kinetic assessments of possible metal fluorides. Anode assessments on graphite and glass‐like carbon demonstrate the effect of the absence of the anode during generation of F2gas owing to stabilized operations at room temperature. Although the Ni anode dissolves during electrolysis in the conventional medium‐temperature cell, herein, it facilitates stable electrolysis over 100 h, achieving an F2gas purity of over 99 % with the potential to operate using one‐compartment electrolysis. This work presents a safe and propitious method for the generation of high‐purity F2gas for small‐scale lab and industrial applications.
Boosting Zinc Electrode Reversibility in Aqueous Electrolytes by Using Low‐Cost Antisolvents
Authors: Hao Junnan , Yuan Libei , Ye Chao , Chao Dongliang , Davey Kenneth , Guo Zaiping , Qiao Shi‐Zhang
Published: January 2021

Antisolvent addition has been widely studied in crystallization in the pharmaceutical industries by breaking the solvation balance of the original solution. Here we report a similar antisolvent strategy to boost Zn reversibility via regulation of the electrolyte on a molecular level. By adding for example methanol into ZnSO4electrolyte, the free water and coordinated water in Zn2+solvation sheath gradually interact with the antisolvent, which minimizes water activity and weakens Zn2+solvation. Concomitantly, dendrite‐free Zn deposition occurs via change in the deposition orientation, as evidenced by in situ optical microscopy. Zn reversibility is significantly boosted in antisolvent electrolyte of 50 % methanol by volume (Anti‐M‐50 %) even under harsh environments of −20 °C and 60 °C. Additionally, the suppressed side reactions and dendrite‐free Zn plating/stripping in Anti‐M‐50 % electrolyte significantly enhance performance of Zn/polyaniline coin and pouch cells. We demonstrate this low‐cost strategy can be readily generalized to other solvents, indicating its practical universality. Results will be of immediate interest and benefit to a range of researchers in electrochemistry and energy storage.
Complementary Syntheses Giving Access to a Full Suite of Differentially Substituted Phthalocyanine‐Porphyrin Hybrids
Authors: Alkorbi Faeza , Díaz‐Moscoso Alejandro , Gretton Jacob , Chambrier Isabelle , Tizzard Graham J. , Coles Simon J. , Hughes David L. , Cammidge Andrew N.
Published: January 2021

Phthalocyanines and porphyrins are often the scaffolds of choice for use in widespread applications. Synthetic advances allow bespoke derivatives to be made, tailoring their properties. The selective synthesis of unsymmetrical systems, particularly phthalocyanines, has remained a significant unmet challenge. Porphyrin‐phthalocyanine hybrids offer the potential to combine the favorable features of both parent structures, but again synthetic strategies are poorly developed. Here we demonstrate strategies that give straightforward, controlled access to differentially substituted meso‐aryl‐tetrabenzotriazaporphyrins by reaction between an aryl‐aminoisoindolene (A) initiator and a complementary phthalonitrile (B). The choice of precursors and reaction conditions allows selective preparation of 1:3 Ar‐ABBB and, uniquely, 2:2 Ar‐ABBA functionalized hybrids.
Cu(OTf)2‐Mediated Cross‐Coupling of Nitriles and N‐Heterocycles with Arylboronic Acids to Generate Nitrilium and Pyridinium Products**
Authors: Bell Nicola L. , Xu Chao , Fyfe James W. B. , Vantourout Julien C. , Brals Jeremy , Chabbra Sonia , Bode Bela E. , Cordes David B. , Slawin Alexandra M. Z. , McGuire Thomas M. , Watson Allan J. B.
Published: January 2021

Metal‐catalyzed C–N cross‐coupling generally forms C−N bonds by reductive elimination from metal complexes bearing covalent C‐ and N‐ligands. We have identified a Cu‐mediated C–N cross‐coupling that uses a dative N‐ligand in the bond‐forming event, which, in contrast to conventional methods, generates reactive cationic products. Mechanistic studies suggest the process operates via transmetalation of an aryl organoboron to a CuIIcomplex bearing neutral N‐ligands, such as nitriles or N‐heterocycles. Subsequent generation of a putative CuIIIcomplex enables the oxidative C–N coupling to take place, delivering nitrilium intermediates and pyridinium products. The reaction is general for a range of N(sp) and N(sp2) precursors and can be applied to drug synthesis and late‐stage N‐arylation, and the limitations in the methodology are mechanistically evidenced.
Visible‐Light‐Induced Intramolecular Double Dearomative Cycloaddition of Arenes
Authors: Zhu Min , Xu Hao , Zhang Xiao , Zheng Chao , You Shu‐Li
Published: January 2021

Herein we report visible‐light‐induced intramolecular double dearomative cycloaddition of arenes. Compared with the well‐known photodimerization of arenes under ultraviolet irradiation, the current reactions are carried out under mild conditions and feature wide substrate scope. A large array of structurally‐diverse polycyclic indoline derivatives is afforded in high yields (up to 98 %) with exclusive diastereoselectivity (>20:1 dr) via dearomative [4+2] or [2+2] pathway.
Asymmetric Carbene‐Catalyzed Oxidation of Functionalized Aldimines as 1,4‐Dipoles
Authors: Wang Guanjie , Zhang Qiao‐Chu , Wei Chenlong , Zhang Ye , Zhang Linxue , Huang Juhui , Wei Donghui , Fu Zhenqian , Huang Wei
Published: January 2021

The use of functionalized aldimines has been demonstrated as newly structural 1,4‐dipole precursors under carbene catalysis. More importantly, enantiodivergent organocatalysis has been successfully developed using carbene catalysts with the same absolute configuration, leading to both (R)‐ and (S)‐ enantiomers of six‐membered heterocycles with quaternary carbon centers. This strategy features a broad substrate scope, mild reaction conditions, and good enantiomeric ratio. DFT calculation results indicated that hydrogen bond C−H⋅⋅⋅F interactions between the catalyst and substrate are the key factors for controlling and even switching the enantioselectivity. These new 1,4‐dipoles can also react with isatin and its imines under carbene catalysis, allowing for access to the spiro oxindoles with excellent enantiomeric ratios.
Spinal subarachnoid haematoma after neuraxial anaesthesia in a patient with polycythaemia vera
Authors: Martins T. , Montenegro L. , Silva A. , Reis H. , Pereira E. , Lucas P.
Published: January 2021

Polycythaemia vera is a common haematological proliferative disorder. It is characterised by uncontrolled red cell production with ensuing peri‐operative vaso‐occlusive and haemorrhagic complications. Spinal haematoma after neuraxial anaesthesia is rare; most cases are associated with technical difficulties or bleeding disorders. Current consensus opinion suggests that neuraxial anaesthesia in patients with polycythaemia vera is safe due to a lower risk of thrombotic events and hypoxaemia compared with general anaesthesia. We report a case of a spinal subarachnoid haematoma after uneventful neuraxial anaesthesia in a patient with optimised polycythaemia vera. Despite an emergent laminectomy, the patient developed permanent motor deficits. This report highlights that although neuraxial anaesthesia is recommended by many authors, patients with polycythaemia vera can paradoxically have an increased haemorrhagic risk from platelet dysfunction and acquired von Willebrand disease. Clinicians proceeding with surgery under neuraxial anaesthesia should appreciate these risks even in patients with normal or apparently elevated thrombotic states. This case also demonstrates that traditional coagulation tests may need to be complemented by pre‐operative platelet function tests and screening for von Willebrand disease. Finally, the importance of the patient participation in the choice of the anaesthesia technique cannot be understated, with specific attention paid to this frequently unrecognised risk.
Recent advancements in organic synthesis catalyzed by graphene oxide metal composites as heterogeneous nanocatalysts
Authors: Soni Jay , Sethiya Ayushi , Sahiba Nusrat , Agarwal Shikha
Published: January 2021

In the last decades, heterogeneous catalysis has emerged as a promising approach for sustainable synthesis. Among this, metal‐based graphene oxide (GO) as catalysts is widely used due to their unique properties such as physical and thermal stability of the catalysts in successive reaction runs and reusability. Metal‐supported GOs are quite prevalent and probably suitable acidic catalysts for both research laboratories and industrial processes. Herein, we have described the catalytic efficiency of various metal‐supported GO catalysts in different organic transformations like oxidation, reduction, multicomponent reactions, alkylation, condensation, dehydration, dehydrogenation, and Suzuki, Heck, and Sonogashira reactions. This article has been divided into three subsections: (i) GO‐supported metal as a catalyst, (ii) GO‐supported bimetal as a catalyst, and (iii) GO‐supported metal oxide as a catalyst for the easier understanding of the vast community of researchers. The foremost aim of this article is to summarize the uses of metal‐supported GO in the preparation of diverse synthetic molecules. The recent advancements in GO metal composites as catalysts with their applications have been deliberated.
Quality Characteristics and Antioxidant Activity during Fruit Ripening of Three Monovarietal Olive Oils Cultivated in China
Authors: Wang Yongjin , Yu Le , Zhao Anni , Karrar Emad , Zhang Hui , Jin Qingzhe , Wu Gangcheng , Yang Xiaoyan , Chen Li , Wang Xingguo
Published: January 2021

Numerous olive cultivars have been planted in China, mainly to reap the health benefits of olive oil. This study characterized the quality and investigated the antioxidant activity of olives harvested at three different maturation stages, defined by the skin color of the olives (black, purple, and green), from three newly introduced olive cultivars (Barnea, Manzanilla and Kadesh) grown in China. The oleic acid content of olives from all three olive cultivars decreased significantly during maturation, whereas the linoleic acid content increased. The highest content of total phenols was recorded in Manzanilla cultivar (284.94 mg kg−1), whereas the lowest was recorded in Kadesh cultivar (134.82 mg kg−1). In addition, a total of 13 individual phenolic compounds were obtained, and their concentrations were significantly influenced by the cultivar and maturity (P < 0.05). Secoiridoids were the main group of phenolic compounds, but their quantity decreased during maturation. The content of secoiridoids in the Manzanilla cultivar was significantly higher than that of the Barnea and Kadesh cultivars. In general, a significant decrease (P < 0.05) in the values of antioxidant activity and the contents of pigments, α‐tocopherol, and squalene occurred during maturation. Furthermore, principal component analysis was used to classify the nine olive oil samples according to the cultivar and ripening degree.
Effect of structure on the glass transition temperatures of linear and crosslinked poly(isobornylacrylate‐co‐isobutylacrylate)
Authors: Zeggai Nouh , Bouberka Zohra , Dubois Frédéric , Bouchaour Tewfik , Dali Youcef Boumediene , Delarace Lea , Potier Jonathan , Supiot Philippe , Maschke Ulrich
Published: January 2021

A series of linear acrylic copolymers based on Isobornyl acrylate (IBOA) and isobutyl acrylate (IsoBA) were elaborated by radical photopolymerization. In addition, several photochemically crosslinked poly(IBOA‐co‐IsoBA) were prepared by introducing small amounts of 1,6‐hexanedioldiacrylate as crosslinking agent. The evolution of the glass transition temperature was determined experimentally by differential scanning calorimetry as a function of composition for both linear and crosslinked poly(IBOA‐co‐IsoBA), yielding Tg values ranging from (~249) to (~315 K). Theoretical modeling was performed applying Fox, Gordon‐Taylor and Couchman‐Karasz models by simple calculations using experimental data, leading to only fair agreement between theoretical and experimental values, or by applying fitting procedures involving one or two adjustable parameters. Likewise, the Kwei model, known to take into account hydrogen bonding interactions between monomers, could not describe well the evolution of Tg, indicating the existence of other factors influencing Tg. Finally, a thermodynamic approach based on entropy considerations allowed to attribute an explanation of the evolution of Tg.
Further evidence needed to change policy for the safe and effective radical cure of vivax malaria: Insights from the 2019 annual APMEN Vivax Working Group meeting
Authors: Ruwanpura Varunika Sonani Hapuwatte , Nowak Spike , Gerth‐Guyette Emily , Theodora Minerva , Dysoley Lek , Haile Mebratom , Peeters Grietens Koen , Price Ric Norman , Lynch Caroline Anita , Thriemer Kamala
Published: January 2021

New diagnostics and treatment options for the radical cure of Plasmodium vivax malaria are now available. At the 2019 annual meeting of the Vivax Working Group of the Asia Pacific Malaria Elimination Network, participants took part in a roundtable discussion to identify further evidence required to introduce these new tools into policy and practice. Key gaps identified were accuracy and reliability of glucose‐6‐phosphate‐dehydrogenase deficiency tests, health system capacity, and feasibility and cost effectiveness of novel treatment strategies in routine clinical practice. As expected, there were differences in the priorities between country partners and researcher partners. To achieve the 2030 target for the regional elimination of malaria, evidence to address these issues should be generated as a matter of priority. Review of global guidelines alongside locally generated data will help to ensure the timely revision and optimisation of national treatment guidelines that will be vital to meet regional elimination goals.
Assessment of a terrestrial protected area for the conservation of freshwater biodiversity
Authors: Nogueira Joana Garrido , Teixeira Amílcar , Varandas Simone , Lopes‐Lima Manuel , Sousa Ronaldo
Published: January 2021

Freshwater ecosystems are essential to human well‐being and most have high biodiversity. However, this biodiversity has been suffering severe declines owing to the expansion of human activities. Protected areas (PAs) are essential for biodiversity conservation and have proved to be successful in stopping species extirpation if managed properly. Unfortunately, they are usually focused on terrestrial biodiversity, leaving freshwater ecosystems aside.

The main goal of this study was to determine the influence of a PA (Montesinho Natural Park (MNP), Portugal) on freshwater biodiversity. Aquatic macroinvertebrates and fishes were surveyed, and biodiversity (richness, abundance, Shannon‐Wiener diversity, and Pielou's evenness) and water quality (IASPT) indices were calculated inside, at the periphery and outside the MNP.

Results showed that the PA does not affect positively either water quality or the two faunal groups monitored. Macroinvertebrate communities were not influenced by the PA; however, the abundance of pearl musselMargaritifera margaritiferawas significantly higher and size was significantly lower inside the MNP. The richness and abundance of fish communities were significantly higher outside the MNP, except for troutSalmo truttaabundance which was higher inside the MNP.

Given these results, the MNP does not guarantee the safeguard of overall aquatic biodiversity and habitats and we propose an extension of MNP to downstream areas in order to increase the number of species (mostly cyprinids) under legal protection. This work demonstrates that terrestrial PA planning and management should also consider aquatic biodiversity to achieve successful conservation.
Synthesis, characterization, crystal structure, α‐glycosidase, and acetylcholinesterase inhibitory properties of 1,3‐disubstituted benzimidazolium salts
Authors: Bal Selma , Demirci Özlem , Şen Betül , Taslimi Parham , Aktaş Aydın , Gök Yetkin , Aygün Muhittin , Gülçin İlhami
Published: January 2021

Chloro‐/fluorobenzyl‐substituted benzimidazolium salts were synthesized from the reaction of 4‐fluorobenzyl/2‐chloro‐4‐fluorobenzyl‐substituted benzimidazole and chlorinated aromatic hydrocarbons. They were characterized using various spectroscopic techniques (Fourier‐transform infrared and nuclear magnetic resonance) and elemental analysis. In addition, the crystal structures of the complexes 1a –d and 2b were determined by single‐crystal X‐ray diffraction methods. These compounds were crystallized in the triclinic crystal system with a P‐1 space group. The crystal packing of all complexes is dominated by O–H⋯Cl hydrogen bonds, which link the water molecules and chloride anions, forming a chloride–water tetrameric cluster. These synthesized salts were found to be effective inhibitors for α‐glycosidase and acetylcholinesterase (AChE), with Ki values ranging from 45.77 ± 6.83 to 102.61 ± 11.56 µM for α‐glycosidase and 0.94 ± 0.14 to 10.24 ± 1.58 µM for AChE. AChE converts acetylcholine into choline and acetic acid, thus causing the return of a cholinergic neuron to its resting state. Discovering AChE and α‐glycosidase inhibitors is one of the important ways to develop new drugs for the treatment of Alzheimer's disease and diabetes.
Raman Imaging: An Impending Approach Towards Cancer Diagnosis
Authors: Ramya Adukkadan N. , Arya Jayadev S. , Madhukrishnan Murali , Shamjith Shanmughan , Vidyalekshmi Murukan S. , Maiti Kaustabh K.
Published: January 2021

In accordance with the recent studies, Raman spectroscopy is well experimented as a highly sensitive analytical and imaging technique in biomedical research, mainly for various disease diagnosis including cancer. In comparison with other imaging modalities, Raman spectroscopy facilitate numerous assistances owing to its low background signal, immense spatial resolution, high chemical specificity, multiplexing capability, excellent photo stability and non‐invasive detection capability. In cancer diagnosis Raman imaging intervened as a promising investigative tool to provide molecular level information to differentiate the cancerous vs non‐cancerous cells, tissues and even in body fluids. Anciently, spontaneous Raman scattering is very feeble due to its low signal intensity and long acquisition time but new advanced techniques like coherent Raman scattering (CRS) and surface enhanced Raman scattering (SERS) gradually superseded these issues. So, the present review focuses on the recent developments and applications of Raman spectroscopy‐based imaging techniques for cancer diagnosis.