The 100 most-cited articles in Chemical Communications, 2021

(ii), Tl(i), Cr(vi), Ag(i), and Cu(ii), we review a variety of recent electrochemical methods for detecting heavy metal ions. Compared with traditional methods, electrochemical methods are portable, fast, and cost-effective, and they can be adapted to various on-site inspection sites. Our review shows that the electrochemical detection of heavy metal ions is a very promising strategy that has attracted widespread attention and can be applied in agriculture, life science, clinical diagnosis, and analysis.

Owing to the high power density and ultralong cycle life, supercapacitors represent an alternative to electrochemical batteries in energy storage applications. However, the relatively low energy density is the main challenge for supercapacitors in the current drive to push the entire technology forward to meet the benchmark requirements for commercialization. To effectively solve this issue, it is crucial to develop electrode materials with excellent electrochemical performance since the electrode used is closely related to the specific capacitance and energy density of supercapacitors. With the unique structure, compositional flexibility, and inherent oxygen vacancy, perovskite oxides have attracted wide attention as promising electrode materials for supercapacitors. In this review, we summarize the recent advances in perovskite oxides as electrode materials for supercapacitors. Firstly, the structures and compositions of perovskite oxides are critically reviewed. Following this, the progress in various perovskite oxides, including single perovskite and derivative perovskite…

, thus impeding their further biomedical applications. This Review focuses on the controlled design strategies of nanoscale COFs (NCOFs), unique properties of NCOFs for biomedical applications, and recent progress in NCOFs for cancer therapy. In addition, current challenges for the biomedical use of NCOFs and perspectives for further improvements are presented.

493/503 have been widely used for labelling LDs, they exhibit unsatisfactory specificity and spectroscopic properties. This feature article reviews the recent advances in organic fluorescent probes for imaging LDs. We first introduce the key points for probe design, including regulating hydrophobicity and enhancing fluorescence quantum yield in LDs. Then, we summarize the structural features and biological applications of some representative LD probes classified by their frameworks. In addition, the current challenges and future research trends for the fluorescent probes of LDs are discussed as well.

The transition towards safer and more sustainable production of polymers has led to a growing body of academic research into non-isocyanate polyurethanes (NIPUs) as potential replacements for conventional, isocyanate-based polyurethane materials. This perspective article focuses on the opportunities and current limitations of NIPUs produced by the reaction between biobased cyclic carbonates with amines, which offers an interesting pathway to renewable NIPUs. While it was initially thought that due to the similarities in the chemical structure, NIPUs could be used to directly replace conventional polyurethanes (PU), this has proven to be more challenging to achieve in practice. As a result, and in spite of the vast amount of academic research into this topic, the market size of NIPUs remains negligible. In this perspective, we will emphasize the main limitations of NIPUs in comparison to conventional PUs and the most significant advances made by others and us to overcome these limitations. Finally, we provide our personal view of where research should be directed to promote the…

In the last decade, photoredox catalysis has unlocked unprecedented reactivities in synthetic organic chemistry. Seminal advancements in the field have involved the use of well-studied metal complexes as photoredox catalysts (PCs). More recently, the synthetic community, looking for more sustainable approaches, has been moving towards the use of purely organic molecules. Organic PCs are generally cheaper and less toxic, while allowing their rational modification to an increased generality. Furthermore, organic PCs have allowed reactivities that are inaccessible by using common metal complexes. Likewise, in synthetic catalysis, the field of photocatalysis is now experiencing a green evolution moving from metal catalysis to organocatalysis. In this feature article, we discuss and critically comment on the scientific reasons for this ongoing evolution in the field of photoredox catalysis, showing how and when organic PCs can efficiently replace their metal counterparts.

Flexible electrochemical supercapacitors have shown great potential in the next-generation wearable and implantable energy-storage devices. Conductive polymer hydrogels usually possess unique porosity, high conductivity, and broadly tunable properties through molecular designs and structural regulations, thus holding tremendous promise as high-performance electrodes and electrolytes for flexible electrochemical supercapacitors. Numerous chemical and structural designs have provided unlimited opportunities to tune the properties of conductive polymer hydrogels to match the various practical demands. Various electrically and ionically conductive hydrogels have been developed to fabricate novel electrodes and electrolytes with satisfactory mechanical and electrochemical performance. This feature article focuses on the fabrication and applications of conductive polymer hydrogel composites and nanocomposites as respective electrodes and electrolytes for flexible electrochemical supercapacitors. First, we introduce the representative strategies to prepare electrically and ionically…

This study reports a photoelectrochemical biosensor for dopamine-loaded liposome-encoded magnetic beads cleaved by clustered regularly interspaced short palindromic repeats (CRISPR)/Cas 12a system for the quantification of human papilloma virus (HPV)-related DNA using neodymium-doped BiOBr nanosheets (Nd-BiOBr) as a photoactive matrix. Magnetic beads and dopamine-loaded liposomes are covalently attached to the both ends of ssDNA to construct dumbbell-shaped dopamine-loaded liposome-encoded magnetic bead (DLL-MB) probes. When the guide RNA binds to the target HPV-16, the ssDNA will be cleaved by Cas12a, thereby degrading the double dumbbell probes. After magnetic separation, the dissolved DLLs are treated with Triton X-100 to release the dopamine (as an electron donor), which was then detected by an amplified photocurrent using the Nd-BiOBr-based photoelectrode.

A two-pronged concept combining photodynamic therapy (PDT) and epithelial-mesenchymal transition (EMT) blockade in a minimalist nanoplatform was proposed to combat basal-like breast cancer (BLBC) metastasis. Based on PDT-mediated tumor killing and epalrestat (Epa)-mediated EMT blockade, as-prepared Ce6/Epa nanoparticles prevented BLBC metastasis effectively in vivo, providing a very promising two-pronged strategy against BLBC metastasis.

Chemical reactions are ubiquitous in the universe, they are at the core of life, and they are essential for industrial processes. The drive for a deep understanding of how something occurs, in this case, the mechanism of a chemical reaction and the factors controlling its reactivity, is intrinsically valuable and an innate quality of humans. The level of insight and degree of understanding afforded by computational chemistry cannot be understated. The activation strain model is one of the most powerful tools in our arsenal to obtain unparalleled insight into reactivity. The relative energy of interacting reactants is evaluated along a reaction energy profile and related to the rigidity of the reactants' molecular structure and the strength of the stabilizing interactions between the deformed reactants: ΔE(ζ) = ΔEstrain(ζ) + ΔEint(ζ). Owing to the connectedness between the activation strain model and Kohn-Sham molecular orbital theory, one is able to obtain a causal relationship between both the sterics and electronics of the reactants and their mutual reactivity. Only when this is…

By rationally choosing Pd as an active metal and Cu as a promoting metal, we developed Cu-rich CuPd bimetallic aerogels as a self-supported electrocatalyst for nitrate electroreduction. The spongy aerogel structure provides abundant catalytically active sites, while the synergistic benefit of the CuPd binary composition increases their reactivity, helping to achieve efficient nitrate-to-ammonia conversion.

Structural colors, generated by the interaction of interference, diffraction, and scattering between incident light and periodic nanostructured surfaces with features of the same scale with incident visible light wavelengths, have recently attracted intense interest.

We report an electroreforming strategy to upcycle waste PET into value-added chemicals and H 2 using Pd as the anode and Ni foam as the cathode.

) based on selectivity-reversed adsorption and multicomponent separation strategies. Moreover, we highlight the advances over the past three years in the field of MOF-based luminescent materials for thermometry, turn-on sensing, and information encryption.

Ammonia is one of the most useful chemicals for the fertilizer industry and is also promising as an important energy carrier for fuel cell application, and is currently mostly produced by the traditional Haber-Bosch process under high temperature and pressure conditions. This energy-intensive process is detrimental to the environment due to the dependence on fossil fuels and the emission of significant greenhouse gases (such as CO2). Ammonia production via the electrochemical nitrogen reduction reaction (ENRR) has been recognized as a green sustainable alternative to the Haber-Bosch process in recent years. Current ENRR research mainly focuses on the catalyst for ammonia selective production and the enhancement of faradaic efficiency at high current density; however, these have not been explored well due to the unavailability of highly efficient and cheap catalysts. Herein, this review provides information on the ENRR process along with (i) theoretical background, (ii) experimental methodology of the electrocatalytic process and (iii) computational screening of promising catalysts.…

Cardiovascular diseases are currently the leading cause of death globally and are projected to remain the leading cause in 2040, making heart rate an important physiological indicator that should be regularly monitored. Current heart rate monitoring techniques, including photoplethysmography and electrocardiography, are inconvenient for continuous biomonitoring in a wearable way. With a collection of compelling features, such as light weight and high sensitivity, triboelectric nanogenerators (TENGs) have become an emerging and cost-effective biotechnology for long-term and continuous heart rate monitoring in a wearable manner. In this review, we systematically discuss the biomechanics of heart beat, working mechanisms of TENGs, and exemplary applications of TENGs for self-powered heart rate monitoring. Finally, we conclude with a discussion of the potential for technology development in the future.

The application of representative C–H activation/functionalization reactions for drug synthesis, late-stage modification of pharmacophores, bioconjugation and representative case studies for accelerated drug discovery is highlighted.

A high loading of Mn( ii )-metalated porphyrin in a MOF for photocatalytic CO 2 reduction in gas–solid conditions is described.

Site-selective protein modification is of significant interest in chemical biology research, with lysine residues representing a particularly challenging target. Whilst lysines are popular for bioconjugation, due to their nucleophilicity, solvent accessibility and the stability of the resultant conjugates, their high abundance means site-selectivity is very difficult to achieve. Antibody-drug conjugates (ADCs) present a powerful therapeutic application of protein modification, and have often relied extensively upon lysine bioconjugation for their synthesis. Here we discuss advances in methodologies for achieving site-selective lysine modification, particularly within the context of antibody conjugate construction, including the cysteine-to-lysine transfer (CLT) protocol which we have recently reported.

in hypoxia than in normoxia in HCC4006 cells. This is the first example of identifying a PROTAC to selectively act on tumors utilizing the characteristic of tumor hypoxia and provides a new approach for PROTAC development.

, antigens/antibodies, enzymes, therapeutic proteins, DNA/RNA, polypeptides, and polysaccharides) for the treatment of various human diseases based on immunotherapy, gene therapy, starvation therapy and oxidation therapy is summarized. Finally, the remaining challenges and available opportunities for MOFs as drug delivery systems are outlined, which we anticipate will encourage additional research efforts directed towards developing Biomacromolecules@MOFs systems for biomedical applications.

Chiral macrocycles possess significant value in chiral science and supramolecular chemistry. Pillararenes, as a class of relatively young supramolecular macrocyclic hosts, have been widely used for host-guest recognition and self-assembly. Since the position of substituents on the benzene rings breaks the molecular symmetry (symmetric plane and symmetric center), pillararenes possess planar chirality. However, it is a great challenge to synthesize stable and resolvable enantiomers because of the easy rotation of the phenylene group. In this review, we summarize the construction methods of resolvable chiral pillararenes. We also focus on their applications in enantioselective recognition, chiral switches, chirality sensing, asymmetric catalysis, circularly polarized luminescence, metal-organic frameworks, and highly permeable membranes. Finally, we discuss the future research perspectives in this field of pillararene-based planar chiral materials. We hope that this review will encourage more researchers to work in this exciting field.

With interest in non-invasiveness and safety in cancer treatment, sonodynamic therapy (SDT) has emerged as a promising alternative to conventional cancer therapies. SDT offers safety and cost-effectiveness and exhibits a broad application range that is superior to photodynamic therapy. However, the insufficient reactive oxygen species (ROS) production of current sonosensitizers has hindered its clinical application to date. In this review, the ROS-generation mechanism in SDT and the limitations of current sonosensitizers are briefly reviewed. Also, highlighted are recent nanomaterial-based SDT strategies to improve the efficiency of sonosensitizers, amplify oxidative stress, and elicit antitumor immunity.

Liquid-liquid phase separation (LLPS), a type of phase transition that is important in organisms, is a unique means of forming biomolecular condensates. LLPS plays a significant role in transcription, genome organisation, immune response and cell signaling, and its dysregulation may cause neurodegenerative diseases and cancers. Exploring the regulatory mechanism of LLPS contributes to the understanding of the pathogenic mechanism of abnormal phase transition and enables potential therapeutic targets to be proposed. Many factors have been found to regulate LLPS, of which post-translational modification (PTM) is among the most important. PTMs can change the structure, charge, hydrophobicity and other properties of the proteins involved in phase separation and thereby affect the phase transition behaviour. In this review, we discuss LLPS and the regulatory effects of PTMs, RNA and molecular chaperones in a phase separation system. We introduce several common PTMs (including phosphorylation, arginine methylation, arginine citrullination, acetylation, ubiquitination and…

The merging of decatungstate photocatalysis with electrochemistry enabled the net-oxidative alkylation of benzothiazoles with aliphatic hydrogen donors featuring strong C(sp 3 )–H bonds.

Light-harvesting, which involves the conversion of sunlight into chemical energy by natural systems such as plants, bacteria, is one of the most universal routine activities in nature. Thus far, various artificial light-harvesting systems (LHSs) have been fabricated toward solar energy utilization through mimicking natural photosynthesis in simplified and altered ways. Macrocycles are supramolecular hosts with unique cavities, in which specific guest molecules can be recognized based on non-covalent interactions. They have been widely employed in constructing LHSs due to their ability to form supramolecular assembly and dynamic molecular activity. In this review, we mainly focus on some representative examples reported by our group and other groups. Specifically, the fabrication of LHSs and their related discussions, such as a high donor/acceptor ratio, driving force for the formation of supramolecular assemblies and energy transfer mechanisms using different water-soluble macrocycles such as cyclodextrins (CD), pillararenes (PA), calixarenes (CA), cucurbiturils (CB), and other…

Photosynthesis and electrosynthesis enable the “green” upcycling of SO 2 to value-added products.

A mitochondria-targeted near-infrared fluorescent probe NIR-V with 700 nm emission was designed to monitor cell viscosity changes with high selectivity and sensitivity, which was applied to detect the intracellular viscosity and image pancreatic tissue in a diabetic mouse model. Probe NIR-V provides an effective way to diagnose viscosity related diseases.

1,2-Dicarbofunctionalization of alkenes represents an appealing strategy for chemical bond formation in organic synthesis, which could enable the rapid construction of molecular complexity from simple and readily available starting materials by incorporating two functional groups onto a carbon-carbon double bond in one step. In this field, the dicarbofunctionalization of alkenes with different alkyl radicals in a controlled manner represents an elegant and versatile strategy to access structurally diverse functionalized alkanes, which have witnessed significant progress over the last five years. Due to the importance of alkyl radicals in organic synthesis and medicinal chemistry, this review provides a comprehensive perspective on the development of alkyl radical precursors including electrophilic precursors such as alkyl halides, alkyl peroxides, alkyl NHP esters, cycloketone oxime esters, and Katritzky pyridinium salts, and nucleophilic precursors such as alkyl acids, alkyl oxalates, alkylborates, alkylsilicates, and unactivated hydrocarbons, which generate alkyl radicals by…

mimic the weak-overlap covalent bonding that is characteristic of M-M interactions, and aliphatic linkers in the ligand backbone provide geometric flexibility, allowing for interconversion between a range of geometries as the dinuclear core responds to the requirements of various small molecule substrates. The union of these design elements appears to be a powerful combination for analogizing critical aspects of heterogeneous and metalloenzyme catalysts.

N-Heterocyclic carbenes (NHCs) are nowadays ubiquitous in organometallic chemistry and catalysis. Recently, a synthetic method which makes use of weak bases and desirable solvents has emerged as a simple, widely applicable and cost-effective pathway to well defined M-NHC complexes. Herein, recent studies devoted to the weak base approach are examined in detail, in order to showcase the simplicity, scope and variations of the method with regards to the azolium salts, bases and the metal sources, as well as the reaction conditions used. Mechanistic investigations are presented, illustrating the formation of intermediates which are air and moisture stable, prior to the metallation step. Finally, the importance, limitations and future prospects of the weak base route are discussed.

Macrocyclic host molecules play the central role in host-guest chemistry and supramolecular chemistry. The highly structural symmetry of macrocyclic host molecules can meet people's pursuit of aesthetics in molecular design, and generally means a balance of design, synthesis, properties and applications. For macrocyclic host molecules with highly symmetrical structures, building blocks, which could be described as repeat units as well, are the most fundamental elements for molecular design. The structural features and recognition ability of macrocyclic host molecules are determined by the building blocks and their connection patterns. Using different building blocks, different macrocyclic host molecules could be designed and synthesized. With decades of developments of host-guest chemistry and supramolecular chemistry, diverse macrocyclic host molecules with different building blocks have been designed and synthesized. Aromatic building blocks are a big family among the various building blocks used in constructing macrocyclic host molecules. In this feature article, the recent…

Alkenes bearing four carbon-based groups are ubiquitous motifs in chemical sciences due to their various applications from medicinal to materials chemistry, and as chemical platforms for the synthesis of complex, chiral molecules. As such, tremendous research efforts are currently ongoing in order to develop general procedures for the challenging stereoselective synthesis of all-carbon tetrasubstituted alkenes, especially for acyclic structures. Since classical approaches to carbon-carbon double bonds are not suitable for the high steric demand around tetrasubstituted alkenes, a variety of unique approaches to access these privileged functional groups have been developed in recent years. This review article highlights the most significant developments in the field from 2007 to 2020, with an emphasis on the mechanisms and remaining limitations of these contemporary methods. Specifically, recent advances in internal alkyne carbofunctionalizations, in multicomponent couplings or other cross-couplings from nucleophilic or electrophilic alkenyl partners, and in the development of…

The trans-cleavage activity of the target-activated CRISPR/Cas12a liberated an RNA crosslinker from a molecular transducer, which facilitated the assembly of gold nanoparticles. Integration of the molecular transducer with isothermal amplification and CRISPR/Cas12a resulted in visual detection of the N gene and E gene of SARS-CoV-2 in 45 min.

Herein, we propose a solvent-assisted approach for preparing Ni-MOF microflowers with high specific capacitance and excellent rate capability as an electrode material for supercapacitors. The high electrochemical performance of this Ni-MOF is attributed to the fast ion transport and low electrical resistance resulting from its hierarchical flower-like structure, and the capacitance contribution from nickel hydroxide species.

Carbanions serve as key intermediates in a variety of chemical transformations. Particularly, α-borylcarbanions have received considerable attention in recent years because of their peculiar properties, including the ability of boron atom resonance to stabilise the adjacent negatively charged carbon atom. This feature article summarises recent progress in the synthetic utilisation of α-borylcarbanions, including carbon-carbon bond formation with alkyl halides, alkenes, N-heteroarenes, and carbonyls. Carbon-boron bond formation in organohalides mediated by α-borylcarbanions is also summarised.

Inducing the immunogenic cell death (ICD) of cancer cells is an important method to improve the immunogenicity of tumor cells for enhanced cancer immunotherapy. Therefore, we discuss the ICD process and then highlight various ICD inducers and strategies for triggering the ICD of cancer cells. We hope that this Feature Article will inspire readers to develop more effective ICD inducers.

Radical-mediated functionalization of alkenes has been emerging as an elegant and straightforward protocol to increase molecule complexity. Moreover, the abstraction of a hydrogen atom from aldehydes to afford acyl radicals has evolved as a rising star due to its high atom-economy and the ready availability of aldehydes. Considering the great influence and synthetic potential of acyl radical enabled reactions between aldehydes and alkenes, we provide a summary of the state of the art in this field with a specific emphasis on the working models and corresponding mechanisms. The discussion is divided according to the kind of alkenes and reaction type.

Oxygen reduction reaction (ORR) plays a pivotal role in electrochemical energy conversion and commodity chemical production. Oxygen reduction involving a complete four-electron (4e-) transfer is important for the efficient operation of polymer electrolyte fuel cells, whereas the ORR with a partial 2e- transfer can serve as a versatile method for producing industrially important hydrogen peroxide (H2O2). For both the 4e- and 2e- pathway ORR, platinum-group metals (PGMs) have been materials of prevalent choice owing to their high intrinsic activity, but they are costly and scarce. Hence, the development of highly active and selective non-precious metal catalysts is of crucial importance for advancing electrocatalysis of the ORR. Heteroatom-doped carbon-based electrocatalysts have emerged as promising alternatives to PGM catalysts owing to their appreciable activity, tunable selectivity, and facile preparation. This review provides an overview of the design of heteroatom-doped carbon ORR catalysts with tailored 4e- or 2e- selectivities. We highlight catalyst design strategies that…

A narrowband blue CP-TADF emitter with a rigid hetero-helicene structure (QAO-PhCz) was synthesized and characterized.

Autophagy-based protein degradation is emerging as a promising technology for anti-diseases and innovative drug discovery. Here, we demonstrate a novel type of autophagy-targeting chimera (AUTAC) to degrade protein by targeting autophagy key protein LC3. The best compound 10f powerfully degraded BRD4 protein through the autophagy pathway and exhibited good anti-proliferative activity in multiple tumor cells, providing a powerful toolbox for medicinal chemists to study disease-related targets with autophagy-based degradation.

Five new zero-dimensional hybrid manganese halides based on discrete [MnCl4]2- tetrahedrons were prepared and used as highly efficient green-light emitters. Through rational management of organic cations to tailor the MnMn separation distances between neighboring [MnCl4]2- tetrahedrons, the photoluminescence quantum yield increased significantly from 7.98% to 81.11%.

Although the chemistry of the group 2 metals has always been dominated by their +II oxidation state, there is an increasing interest in their low-valent complexes. Recent developments include zero-valent complexes and observation of N 2 fixation.

inner-sphere anodic reactions, which are strongly dependent on the nature of the electrode material. Particularly, the understanding of the formation of reactive oxygen species, adsorption of substrates, and reconstruction of anode materials is presented. Finally, the existing challenges and perspectives are discussed.

The highlight describes the emerging trend in the C–F functionalization area: recent progress in the single-electron-transfer initiated selective defluorinative functionalizations of C sp 3 –F bonds in multifluorinated compounds via radical pathways.

appropriate tuning of ligands or a slight modification of reaction conditions. Herein, we have provided a comprehensive overview of the chain-walking reactions involving a variety of catalytic systems ranging from the first-row transition metal catalysts to the third-row transition metal catalysts for C-H activation in a concise fashion with the hope for further developments in this area through the appropriate application of the chain-walking reactions.

π-Conjugated-polymer-based nanofibers (CPNFs) of controlled length, composition and morphology are promising for a broad range of emerging applications in optoelectronics, biomedicine and catalysis, owing to the morphological merits of fiber-like nanostructures and structural attributes of π-conjugated polymers. Living crystallization-driven self-assembly (CDSA) of π-conjugated-polymer-containing block copolymers (BCPs) has emerged as an efficient strategy to prepare CPNFs with precise dimensional and structural controllability by taking advantage of the crystallinity of π-conjugated polymers. In this review, recent advances in the generation of CPNFs have been highlighted. The influence of the structure of π-conjugated-polymer-containing BCPs and experimental conditions on the CDSA behaviors, especially seeded growth and self-seeding processes of living CDSA, has been discussed in detail, aiming to provide an in-depth overview of living CDSA of π-conjugated-polymer-containing BCPs. In addition, the properties of CPNFs as well as their potential applications have been illustrated.…

Nitrile or cyano compounds are an important part of structural motifs in dyes, agrochemicals, medicinal compounds, and electronic materials. Also, aryl nitrile is an important intermediate in the preparation of numerous compounds via transformations such as hydrolysis, hydration, reduction, cycloadditions, and nucleophilic additions. Such methods are beneficial for introducing sensitive functional groups in various positions in the multi-step synthesis of natural products and medicinal compounds. In the past decades, various cyanation methods have been reported in the vast arena of chemistry, which have made several building blocks accessible. Previously reported cyanation reviews, letters, and perspectives are written in parts. Thus, today a comprehensive review that will be able to guide readers through the vast pool of C-CN bond forming reactions via different approaches is obligatory. The present feature article depicts the various areas of cyanation methodologies that are based on the metal catalyst used, directed, non-directed, electrochemical, photochemical, asymmetric, and…

A color and fluorescence turn-on H2S probe is synthesized, achieving real-time detection of H2S in pure water solution with high selectivity. Importantly, the probe is able to sense H2S gas in air via the probe-deposited test paper, which has been successfully used for food spoilage identification.

We give an overview of the molecular response to an external magnetic field perturbing quantum mechanical systems. We present state-of-the-art methods for calculating magnetically-induced current-density susceptibilities. We discuss the essence and properties of current-density susceptibilities and how molecular magnetic properties can be calculated from them. We also review the theory of spin-current densities, how relativity affects current densities and magnetic properties. An overview of the magnetic ring-current criterion for aromaticity is given, which has implications on theoretical and experimental research. The recently reported theory of antiaromaticity and how molecular symmetry affects the magnetic response are discussed and applied to closed-shell paramagnetic molecules. The topology of magnetically induced current densities and its consequences for molecular magnetic properties are also presented with twisted and toroidal molecules as examples.

Ti plate supported cobalt-phosphorus alloy film acts as an active and selective electrocatalyst for ambient NO 3 − -to-NH 3 conversion. In 0.2 M Na 2 SO 4 with 200 ppm NO 3 − , it offers a NH 3 yield rate of 416.0 ± 7.2 μg h −1 cm −2 with a Faradaic efficiency of 93.6 ± 3.3% at −0.6 and −0.3 V vs. RHE, respectively.

generation of various radical species in the photoredox catalytic cycles. Numerous chemically and biomedically valuable building blocks have been synthesized through this efficient and sustainable protocol. In this review, we highlight the recent progress in this blooming area by presenting a series of new catalytic cascade reactions mediated by organic photoredox catalysts and describe their mechanisms and applications which have appeared in the recent literature.

-phenylenediamine (OPD) as a chromogenic substrate to study oxidase- and peroxidase-like mimetics. Based on our findings, we developed a simple epinephrine colorimetric biosensor with a broad linear range (1-100 μM) and a low detection limit (0.298 μM). This approach provides evidence for transition metal-based pristine bi-metallic MOFs capable of reproducing both oxidase-peroxidase properties, which could be applied as new nanosensors.

An acetonitrile/water-in-salt (AWIS) hybrid electrolyte was developed for Zn-ion batteries. Compared to conventional aqueous electrolytes, the AWIS hybrid electrolyte prolonged the lifespan of Zn|Zn cells from 150 to 2500 h and increased the upper cut-off voltage from 1.8 to 2.2 V for Zn-MnO2 batteries. This new AWIS hybrid electrolyte is expected to enhance the energy and power density of Zn-based batteries for large-scale grid storage.

Over the last decade, high-valent cobalt catalysis has earned a place in the spotlight as a valuable tool for C-H activation and functionalization. Since the discovery of its unique reactivity, more and more attention has been directed towards the utilization of cobalt as an alternative to noble metal catalysts. In particular, Cp*Co(III) complexes, as well as simple Co(II) and Co(III) salts in combination with bidentate chelation assistance, have been extensively used for the development of novel transformations. In this review, we have demonstrated the existing trends in the C-H functionalization methodology using high-valent cobalt catalysis and highlighted the main challenges to overcome, as well as perspective directions, which need to be further developed in the future.

High-quality CoP nanorings (CoP NRs) show high activity towards the nitrate electrocatalytic reduction reaction due to substantial coordinately unsaturated active sites, a high surface area, and available mass transfer pathways.

We demonstrate that the capacity decay and voltage drop issues of the Li3V2(PO4)3 cathode are significantly addressed by using a concentrated aqueous electrolyte based on Zn and Li salts. The resultant aqueous Zn//Li3V2(PO4)3 battery achieves a high output voltage of 1.75 V and a long lifespan with 82.3% capacity retention over 2000 cycles. Joint structural and spectroscopic characterizations reveal that this battery operates through Li+ (de)intercalation into the cathode along with Zn2+ plating/stripping at the anode.

Type II heterostructures consisting of red/yellow g-C 3 N 4 nanosheets prepared via edge-epitaxial growth revealed superior photocatalytic activities for enhanced H 2 generation and CO 2 reduction.

A novel and green strategy for the synthesis of acylated quinazolinone derivatives via photo-induced decarboxylative cascade radical acylation/cyclization of quinazolinone bearing unactivated alkenes has been developed. The protocol provides a novel route to access acyl radicals from α-keto acids through a self-catalyzed energy transfer process. Most importantly, the reaction proceeded smoothly without any external photocatalyst, additive or oxidant, and could be easily scaled-up in flow conditions with sunlight irradiation.

The design and construction of an artificial light-harvesting system in water by mimicking the energy transfer cascade in natural photosynthesis are of significant importance. Herein, we report an efficient two-step sequential energy transfer system based on quadruple hydrogen-bonded supramolecular polymeric nanoparticles. By loading two types of hydrophobic dyes as energy acceptors, excitation energy from the supramolecular polymer could be funneled efficiently to the final acceptor through the relay acceptor. The system exhibits tunable multicolor emission from blue through yellow to red, as well as white light emission.

A green biopolymer, lignosulfonate acid (LSA), was first used as an additive in the Nafion membrane for fuel cell applications. The Nafion/LSA composite membrane displayed enhanced thermal stability and other satisfactory properties due to the stable aromatic groups and multiple active sites of LSA. More importantly, the cost-effectiveness and simple fabrication of such novel composite PEMs make their use in PEMFCs very attractive and economical.

A simple and general strategy to construct photo-crosslinkable polymers by introducing sidechain 1,2-dithiolanes based on natural thioctic acid is presented. The disulfide five-membered rings act both as light-absorbing and dynamic covalent crosslinking units, enabling efficient photo-crosslinking and reversible chemical decrosslinking of polydimethylsiloxane polymers.

(L^X) structure type is among the most widely studied and technologically successful classes of molecular phosphors, particularly when L^X = acetylacetonate (acac). In our work we have pioneered the use of electron-rich, nitrogen containing ancillary (L^X) ligands as a means of controlling the excited-state dynamics and optimizing them to give record-breaking phosphorescence quantum yields. This paper progresses through our work in three distinct regions of the spectrum - red, deep-red, and near-infrared - and summarizes the many insights we have gained on the relationships between molecular structure, frontier orbital energies, and excited-state dynamics.

borylation reactions for a diverse class of substrates have also been discussed. The discussion part of several other pioneering reports is limited due to the lack of scope of this feature article.

Layered polyaniline intercalated V 2 O 5 with an expanded layer of ∼1.55 nm exhibits an extremely high ammonium storage capacity.

The solvation structure of Li ions was manipulated. NO 3 − became the main component in the first solvation shell.

A NiO nanosheet array is active for NH 3 electrosynthesis via a NO reduction reaction, attaining a faradaic efficiency of 90% and an NH 3 yield of 2130 μg h −1 cm −2 . Its aqueous Zn–NO battery offers a power density of 0.88 mW cm −2 and an NH 3 yield of 228 μg h −1 cm −2 .

and ligand K edges and we show that the methods are able to (a) provide fingerprint information on the actinide oxidation state and ground state characters (b) probe 5f occupancy, non-stoichiometry, defects, and ligand/metal ratio and (c) investigate the local symmetry and effects of the crystal field. We discuss the chemical aspects of the electronic structure in terms familiar to chemists and materials scientists and conclude with a brief description of new opportunities and approaches to improve the experimental methodology and theoretical analysis for f-electron systems.

Cationic bismuth(iii) species [BiR2]+ with weakly coordinating counteranions feature two monoanionic ligands R (such as aryls, amides, alcoholates or halides), a vacant bismuth-centred p-orbital, and an occupied bismuth-centred s-orbital. The vacant orbital is available for intra- and intermolecular σ- and π-type bonding interactions and plays a crucial role in redox chemistry. The occupied s-orbital may also show minor contributions to dative bonding and is essential when addressing reversible Bi(iii)/Bi(v) redox shuttling. Variation of the anionic ligands R, the weakly coordinating counter anions, and potential neutral ligands L allows precise fine-tuning of the coordination chemistry, Lewis acidity, redox-properties, and reactivity towards nucleophiles. This contribution summarises the fundamental properties of well-defined molecular cationic bismuth compounds and highlights recent advancements in the understanding of their Lewis acidity, in their utilisation for challenging stoichometric reactions (such as CH activation and small molecule activation), and in catalytic…

Unlike the conventional model of transition metal catalysis, ligands in metal-ligand cooperative (or bifunctional) catalysis are involved in the substrate activations. Such processes have offered unique mechanistic understandings and led to new concepts for the catalyst design. In particular, unprecedented activities were discovered when the ligand could undergo dearomatization-rearomatization reactions during the catalytic cycle. Aromatization can provide an extra driving force to thermodynamics; consequently, it brings a new perspective to ligand platform design for catalysis. While numerous applications were demonstrated, the influences of changing ligand aromatic properties were often overlooked. In this article, representative ligand systems will be highlighted and a comparison between the Milstein and the Huang pincer systems will be discussed to provide theoretical and conceptual insights.

A rocking-chair aqueous proton battery is assembled by using dipyridophenazine and indium hexacyanoferrate as the anode and cathode materials, respectively. The reversible amination of redox-active phenazine moieties in dipyridophenazine and fast intercalation-deintercalation of protons in hexacyanoferrate enable the aqueous proton battery to achieve a reversible specific capacity of 37 mA h g-1 at 1 A g-1, good cycling stability with 76.1% capacity retention over 3000 cycles and excellent rate capability.

We review the recent developments in the chemistry of transition-metal difluorocarbenes, including bonding and utility of MCF 2 complexes.

CaCl 2 @COF hybrid materials have been designed and prepared to exhibit a record capacity for ammonia capture and excellent recyclability.

Structurally coloured polymer films with circularly polarized luminescence (CPL) properties were prepared by the photopolymerization of cholesteric liquid crystal mixtures doped with aggregation-induced emission (AIE)-active tetraphenylethylene. The films show good CPL performance with the luminescence dissymmetry factor up to 0.58 and enhanced fluorescence efficiency.

A facile strategy was introduced for room-temperature controllable synthesis of hierarchically flower-like hollow COFs (FHF-COFs). Furthermore, the universality for synthesis of the HFH-COFs was validated by altering the building units. Inspired by the unique morphology, extremely large surface area and good chemical stability, HFH-COFs could serve as an attractive adsorption probe by loading with gold nanoparticles and be applied to enrichment of brain natriuretic peptide from human serum. This work opens up a whole new approach for controllable synthesis of the HFH-COFs at room temperature and expands the application of COFs as a promising enrichment probe for complex biological samples.

Four novel two-dimensional porphyrin COFs (M-TP-COF, M = H 2 , Co, Ni and Mn) with donor–acceptor dyads were fabricated and served as electrocatalysts for the oxygen reduction reaction (ORR).

Catalytic hydrogen transfer reactions have enormous academic and industrial applications for the production of diverse molecular scaffolds. Over the past few decades, precious late transition-metal catalysts were employed for these reactions. The early transition metals have recently gained much attention due to their lower cost, less toxicity, and overall sustainability. In this regard, manganese, which is the third most abundant transition metal in the Earth's crust, has emerged as a viable alternative. However, the key to the success of such manganese-based complexes lies in the multifunctional ligand design and choice of appropriate ancillary ligands, which helps them mimic and, even in some cases, supersede noble metals' activities. The metal-ligand bifunctionality, achieved via deprotonation of the acidic C-H or N-H bonds, is one of the powerful strategies employed for this purpose. Alongside, the ligand hemilability in which a weakly chelating group tunes in between the coordinated and uncoordinated stages could effectively stabilize the reactive intermediates, thereby…

, pH, redox potential, glucose, and hypoxia) for controlled drug delivery applications. The material designs, synthetic strategies, loading and controlled-release mechanisms of drugs, and biomedical applications of these stimuli-responsive polypeptides-based drug delivery systems are elaborated. Finally, the challenges and opportunities in this field are briefly discussed.

-difunctionalization, annulation, cycloaddition and oxidative reactions to construct numerous key building blocks of natural and pharmaceutically important molecules. In addition, the introduction of photoredox chemistry has successfully been used to deal with the challenges associated with alkyne functionalization such as stereoselective and regioselective control. This article accounts for several visible light mediated functionalization reactions of alkynes, wherein they have been transformed into α-oxo compounds, β-keto sulfoxides, substituted olefins, N-heterocycles, internal alkynes and sulfur containing compounds. The article has been primarily categorized into various sections based on the reaction type with particular attention being paid to mechanistic details, advancement and future applications.

Dual-confined porous Si@c-ZIF@carbon nanofibers (Si@c-ZIF@CNFs) are fabricated that possess excellent antioxidant capacity, high surface area and abundant pores, which enhances conductivity, relieves volume expansion and facilitates electrolyte penetration during cycling. When evaluated as self-supporting anodes for lithium-ion batteries, the Si@c-ZIF@CNFs exhibit excellent cycling and rate performance.

Organic electrochemistry is receiving renewed attention as a green and cost-efficient synthetic technology. Electrochemical methods promote redox transformations by electron exchange between electrodes and species in solution, thus avoiding the use of stoichiometric amounts of oxidizing or reducing agents. The rapid development of electroorganic synthesis over the past decades has enabled the preparation of molecules of increasing complexity. Redox steps that involve hazardous or waste-generating reagents during the synthesis of active pharmaceutical ingredients or their intermediates can be substituted by electrochemical procedures. In addition to enhance sustainability, increased selectivity toward the target compound has been achieved in some cases. Electroorganic synthesis can be safely and readily scaled up to production quantities. For this pupose, utilization of flow electrolysis cells is fundamental. Despite these advantages, the application of electrochemical methods does not guarantee superior sustainability when compared with conventional protocols. The utilization of…

Merging two powerful methodologies, metallaphoto-catalyzed benzylic and allylic C(sp 3 )–H bond functionalizations provide a series of general and mild approaches for diversification of alkylbenzenes and alkenes.

Acetalated dextran (Ac-DEX) is a pH-responsive dextran derivative polymer. Prepared by a simple acetalation reaction, Ac-DEX has tunable acid-triggered release profile. Despite its relatively short research history, Ac-DEX has shown great potential in various therapeutic applications. Furthermore, the recent functionalization of Ac-DEX makes versatile derivatives with additional properties. Herein, we summarize the cutting-edge development of Ac-DEX and related polymers. Specifically, we focus on the chemical synthesis, nano- and micro-particle fabrication techniques, the controlled-release mechanisms, and the rational design Ac-DEX-based of drug delivery systems in various biomedical applications. Finally, we briefly discuss the challenges and future perspectives in the field.

) (Pn = P, As) in combination with Al(I) synthons afforded the first examples of phospha- and arsaalumenes as isolable and thermally robust compounds. This feature article is intended to show the recent developments in the field, to outline early synthetic approaches and to discuss strategies to unlock the synthetic potential of these elusive chemical bonds.

An overview of the latest developments in the metal-free synthesis of non-benzo-fused N-functionalized and NH-1,2,3-triazoles is provided in this feature article. Synthetic studies that appeared from 2016 until August 2020 are organized according to a wide-ranging classification, comprising oxidative and eliminative azide-dipolarophile cycloadditions, diazo transfer reactions and N-tosylhydrazone-mediated syntheses. The newly developed methods constitute a significant contribution to the field of 1,2,3-triazole synthesis in terms of structural variation via either the exploration of novel reactions, or the exploitation of existing methodologies.

Thermoelectric materials which can convert heat energy to electricity rely on crystalline inorganic solid state compounds exhibiting low phonon transport (i.e. low thermal conductivity) without much inhibiting the electrical transport. Suppression of phonons traditionally has been carried out via extrinsic pathways, involving formation of point defects, foreign nanostructures, and meso-scale grains, but the incorporation of extrinsic substituents also influences the electrical properties. Crystalline materials with intrinsically low lattice thermal conductivity (κlat) provide an attractive paradigm as it helps in simplifying the complex interrelated thermoelectric parameters and allows us to focus largely on improving the electronic properties. In this feature article, we have discussed the chemical bonding and structural aspects in determining phonon transport through a crystalline material. We have outlined how the inherent material properties like lone pair, bonding anharmonicity, presence of intrinsic rattlers, ferroelectric instability, weak and rigid substructures, etc.…

sensing performance was attributed to the visible-light-activation effects. This study provides a promising method to fabricate room-temperature high-performance gas sensors based on 2D nanomaterials.

, reactive oxygen species, ions, amino acids, and enzymes). The dynamic fluctuations of these bio-molecules in subcellular microenvironments control cellular homeostasis, immunity, signal conduction, and metabolism. Their abnormal expressions are linked to various biological disorders and disease states. Thus, the real-time monitoring of such bioactive species is intimately linked to clinical diagnostics. Appropriately designed luminescent probes are ideally suited for desired organelle specificity, as well as for reporting intracellular changes in biochemicals/microenvironmental factors with the luminescence ON response. In this perspective, we review our recent work on the development of fluorescent probes for sensing and imaging within sub-cellular organelles. We have also discussed the design aspects for developing a prodrug with a fluorescent probe as an integral part of possible theranostic applications. An overview of the design principles, photophysical properties, detection mechanisms, current challenges, and potential future directions of fluorescent probes is presented in…

A series of halogen bonding and chalcogen bonding phenanthroline containing heteroditopic macrocyclic receptors exhibit cooperative recognition of lithium halide (LiX) ion-pairs. Quantitative 1H NMR ion-pair titration experiments in CDCl3 : CD3CN (1 : 1, v/v) reveal a co-bound lithium cation switches on halide anion binding, most notably with the halogen bonding host system. The employment of bis- iodo- and telluromethyl-triazole sigma-hole donor motifs endows contrasting halide anion selectivity and binding affinity, with the halogen bonding ditopic host capable of exclusively binding lithium chloride whereas the chalcogen bonding ditopic receptor displays notable selectivity for lithium iodide over lithium bromide. Preliminary solid-liquid extraction experiments demonstrate the potential of sigma-hole mediated ion-pair recognition as a promising strategy for lithium salt recovery.

Herein, we present the chemistry of isolable monatomic silicon(0) and germanium(0) complexes, highlighting their synthesis, structure, and reactivity, with a particular focus on the cyclic bis-carbene- and bis-silylene-supported silylones and germylones.

Thermal management plays a key role in improving the energy efficiency and sustainability of future building envelopes. Here, we focus on the materials perspective and discuss the fundamental needs, current status, and future opportunities for thermal management of buildings. First, we identify the primary considerations and evaluation criteria for high-performance thermal materials. Second, state-of-the-art thermal materials are reviewed, ranging from conventional thermal insulating fiberglass, mineral wool, cellulose, and foams, to aerogels and mesoporous structures, as well as multifunctional thermal management materials. Further, recent progress on passive regulation and thermal energy storage systems are discussed, including sensible heat storage, phase change materials, and radiative cooling. Moreover, we discuss the emerging materials systems with tunable thermal and other physical properties that could potentially enable dynamic and interactive thermal management solutions for future buildings. Finally, we discuss the recent progress in theory and computational design from…

The synthesis and Pd-catalyzed cross-couplings of structure-modified (hetero)aryl germatranes and alkyl carbagermatranes have been established.

]arene-based porous materials. We hope this article can provide a timely and valuable reference for researchers interested in synthetic macrocycles and porous materials.

Advanced data analysis tools such as mathematical optimisation, Bayesian inference and machine learning have the capability to revolutionise the field of quantitative voltammetry. Nowadays such approaches can be implemented routinely with widely available, user-friendly modern computing languages, algorithms and high speed computing to provide accurate and robust methods for quantitative comparison of experimental data with extensive simulated data sets derived from models proposed to describe complex electrochemical reactions. While the methodology is generic to all forms of dynamic electrochemistry, including the widely used direct current cyclic voltammetry, this review highlights advances achievable in the parameterisation of large amplitude alternating current voltammetry. One significant advantage this technique offers in terms of data analysis is that Fourier transformation provides access to the higher order harmonics that are almost devoid of background current. Perspectives on the technical advances needed to develop intelligent data analysis strategies and make them…

Two 2-dimensional covalent organic frameworks (COFs; TJNU-203 and TJNU-204) with high crystallinity and large specific surface area are rationally fabricated using a three-connected distorted building block and linear linkers. The two COFs show high iodine uptake (5.885 g g-1 for TJNU-203 and 5.335 g g-1 for TJNU-204) on account of physical-chemical adsorption, which make them one among the best porous materials for iodine adsorption.

Mesoporous CoS/MoS2 with abundant heterogeneous interfaces was faciley synthesized from a bimetallic hybrid zeolitic imidazolate framework, which showed excellent catalytic activity and reaction kinetics in both the HER and OER in 1 M KOH. Meanwhile, as a cathode and anode in water splitting electrocatalysis, it delivers a low cell voltage of 1.61 V at 10 mA cm-2 and excellent durability.

)-ones and indolin-2-ones were obtained in one pot with germanium hydrides as radical precursors. A rapid intramolecular radical trapping mode enabled the selective arylgermylation of alkenes over the prevalent hydrogermylation reaction.

Bicyclo[1.1.1]pentane (BCP) is widely applied as the bioisostere for aryl, internal alkynes, and tert-butyl groups in medicinal chemistry. We herein disclose an efficient and practical preparation of sulfonyl alkynyl/allyl/cyano-substituted BCP derivatives through a novel radical-mediated difunctionalization of propellane. The radical alkynylation, allylation, and cyanation processes readily proceed under mild photochemical conditions. The synthetic method features broad functional group tolerance, high product diversity, gram-scale preparation, and excellent atom-economy.

The naphthalimide-derived hypochlorite fluorescent Probe A with ACQ effect was transformated into Probe B possessing AIE characteristics.

We report an alternating-reduction approach by galvanic replacement and co-reduction to enable incorporation of Pd into Pt shell, and the obtained PtPd hollow nanocubes with an enhanced alloy effect and highly active {100} facets show high catalytic activity and superior durability in the methanol oxidation reaction.