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The Co/CoO nanoparticles armored by porous N-doped carbon polyhedrons were successfully prepared from ZIF-67 via a pyrolysis-reorganization method, demonstrating excellent sensing performance towards glucose oxidation.

We highlighted the recent advances in the field of multiple-fold C–F bond functionalization for the synthesis of (hetero)cyclic compounds.

A simple and practical Cs2CO3-promoted method for the synthesis of 6-nitroindole derivatives from enaminones and nitroaromatic compounds has been developed.

A non-enzymatic sensor based on Ag nanoparticle-decorated MoSe2 (Ag/MoSe2-500) hybrid nanostructures exhibited high sensitivity, wide linear range, low detection limit and satisfactory practicality in milk and juice samples.

In this study, we fabricated a novel non-enzymatic glucose sensor based on prism-like bimetallic alkaline carboxylate (CoNi-MIM). The morphology and structure of CoNi-MIM were carefully investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The electrochemical glucose oxidation of the synthesized sensor was then explored by cyclic voltammetry (CV) and chronoamperometry in alkaline medium. It was found that CoNi-MIM is the optimal choice with a remarkably high sensitivity of 5024.4 μA mM

Phosphotungstic acid covered with CeO

Metal–organic frameworks (MOFs) as porous materials have significantly improved catalytic properties because of their rich active sites and large surface area. Herein, we develop a facile and efficient diffusion-controlled strategy to prepare ZIF-67 hollow nanoprisms (ZIF-67 HNPs) for a non-enzymatic glucose sensor. The interparticle pores of the hollow structure can afford fast diffusion pathway for guest molecules to move in and out of the MOF crystals. Such nanostructured MOF-based sensors exhibit good electrocatalytic activity towards glucose oxidation in an alkaline solution with a high sensitivity of 445.7 μA mM−1 cm−2, a low detection limit of 0.96 μM (S/N = 3) and a upper limit of 42.1 mM, and can be used to directly determine blood glucose. Moreover, it achieves well-pleasing results in the non-enzymatic analysis of glucose in real human blood serum samples. In addition, the as-prepared sensor also displays satisfactory reproducibility, selectivity and long-term storage stability. This study focuses on a facile strategy to design the in situ growth of hollow MOF nanomaterials as efficient and stable electrocatalysts, shedding light on the development of non-enzymatic sensors for monitoring glucose with transition metal-based hollow MOF catalysts.

Hollow prism-like NiCo2S4 materials (NiCo2S4 HNPs) were successfully fabricated by a two-step method. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and powder X-ray diffraction (XRD) confirmed the morphology and structure of the as-prepared NiCo2S4 nanoprisms. A non-enzymatic sensor based on NiCo2S4 HNPs was constructed with outstanding electrochemical activity towards glucose oxidation in alkaline medium. The sensor showed a rapid response time (∼0.1 s), a high sensitivity of 82.9 μA mM−1 cm−2, a wide linear range (0.005–20.2 mM) and a detection limit of 0.8 μM (S/N = 3) with a good selectivity and reproducibility. Additionally, the proposed electrode also confirmed the feasibility in practical blood serum. These results indicate that NiCo2S4/ITO has great potential in the development of non-enzymatic glucose sensor applications.

A straightforward aerobic oxidative esterification of aryl aldehydes with alcohols has been developed for the synthesis of substituted esters by employing vitamin B1 as a cost-effective, metal-free, and eco-friendly NHC catalyst. Air is used as a green terminal oxidant. The reaction is a useful addition to the existing NHC-catalytic oxidative esterification.

Synthetic strategies by making use of one-pot multi-step cascade reactions are of special interest. Herein, an efficient three-component tandem reaction of polyfluoroalkyl peroxides with sulfinates for the facile construction of fluoroalkylated tetrasubstituted furan derivatives has been developed. The combination of DABCO and Cs2CO3 was found to be essential for the success of the reaction. This modular and regioselective approach proceeded via an unprecedented sequence of successive defluorination, dual sulfonylation, and annulation relay, along with four C(sp3)–F bonds cleaved and two new C–S bonds formed. In addition, this transition metal-free C–F bond functionalization which is amenable to gram-scale synthesis occurred under mild reaction conditions and has broad substrate scope and excellent functional group tolerance. Moreover, this defluorinative protocol also enabled the late-stage functionalization of complex compounds, which could potentially find synthetic utility in drug discovery.

Ag nanoparticles (Ag NPs) with high electrocatalytic activity are of great significance for electrochemical sensors. Nanostructures as scaffold can solve aggregation problem of Ag NPs so that to ensure the stability. In this work, Ag NPs immobilized on FeS

Hollow prism-like NiCo

As the "chemical chameleon", sulfonyl-containing compounds and their variants have been merged with various types of reactions for the efficient construction of diverse molecular architectures by taking advantage of their incredible reactive flexibility. Currently, their involvement in radical transformations, in which the sulfonyl group typically acts as a leaving group via selective C-S, N-S, O-S, S-S, and Se-S bond cleavage/functionalization, has facilitated new bond formation strategies which are complementary to classical two-electron cross-couplings via organometallic or ionic intermediates. Considering the great influence and synthetic potential of these novel avenues, we summarize recent advances in this rapidly expanding area by discussing the reaction designs, substrate scopes, mechanistic studies, and their limitations, outlining the state-of-the-art processes involved in radical-mediated desulfonylation and related transformations. With a specific emphasis on their synthetic applications, we believe this review will be useful for medicinal and synthetic organic chemists who are interested in radical chemistry and radical-mediated desulfonylation in particular.

An efficient iron-catalyzed C–O bond functionalization of butyrolactam derivatives with various N-/C-nucleophiles to enable the synthesis of pharmaceutically important butyrolactam derivatives has been developed here. The versatility of the present methodology is demonstrated for direct amination and carbonation by using a variety of sulfonamides, amines, amides, indoles, and 1,3-dicarbonyl compounds under mild conditions. The reaction also showed a wide substrate scope and synthetic simplicity. Additionally, only alcohol was produced as the by-product in all cases.

A novel type of porous Co3O4 hollow nanoprism (HNP) was successfully prepared using tetragonal cobalt acetate hydroxide [Co5(OH)2(OAc)8·2H2O] as precursor by a facile solvothermal process and a subsequent calcination treatment. The morphology and structure of the Co3O4 HNPs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD) and N2 adsorption–desorption measurements. An enzyme-free glucose sensor was constructed based on the Co3O4 HNPs, and the electrochemical performance was tested by cyclic voltammetry (CV) and chronoamperometry. The as-prepared sensor exhibited a good electrocatalytic activity for glucose oxidation at the applied potential of 0.6 V in alkaline solution, with a high sensitivity of 19.83 μA mM−1 cm−2 and a high upper limit of 30 mM, which provide the potential for direct determination of blood glucose without any dilution pretreatment. The Co3O4 HNPs had a porous and tubular structure with a large amount of accessible active sites, which enhanced the mass diffusion and accelerated the electron transfer. Moreover, the sensor also demonstrated a desirable stability, selectivity and reproducibility, and could verify the non-enzymatic analysis of glucose in real samples.

A three-component [3 + 2 + 1] annulation strategy for the synthesis of biologically and pharmaceutically active 2,3-diarylpyridine derivatives by using a series of allylic alcohols, ketones, and ammonium acetate as substrates has been developed. The method proceeds efficiently under metal-free conditions, and the desired heterocycles could be obtained in a site-specific selectivity manner with good functional group tolerance.

A novel type of porous Co

Oxidant-directed chemoselective sulfonylation and sulfonyloximation reactions for the divergent synthesis of valuable vinyl sulfones and α-sulfonylethanone oximes starting from simple alkenes and TosMIC by using tert-butyl hydroperoxide and tert-butyl nitrite, respectively, as terminal oxidants were developed. The success of this method could be attributed to the combination of a cobalt catalyst and a perfluoroalkyl halide additive. The feasibility of performing the reactions on a large scale potentially allows the further application of the method in industrial manufacture. Nanyang Technological University We gratefully acknowledge the financial support from the Natural Science Foundation of Jiangsu Province (BK20180690), the Nanjing Tech University (Start-up Grant No. 39837101, 39837118, and 39837146), the SICAM Fellowship from Jiangsu National Synergetic Innovation Center for Advanced Materials, and the Nanyang Technological University.

An efficient copper-catalyzed three-component cyclization for the construction of highly functionalized pyrimidine derivatives from readily available amidines, styrenes and fluoroalkyl halides is developed. This protocol distinguishes itself by the formation of three new C-C/C-N bonds and a new six-membered ring through a radical addition/oxidation/cyclization sequence in a one-pot manner.

Chemoselective functionalizations of intrinsically less reactive C(sp3)–H bonds of alkyl nitriles are of particular interest to the chemical community because these strategies provide opportunities for the introduction of important cyanoalkyl groups onto target frameworks in a step-economical fashion. In recent years, the introduction of nitrile-containing alkyl radicals in tandem radical additions and oxidative couplings has inarguably brought chemists a new radical reaction platform for the diverse synthesis of natural products and pharmaceuticals. Compared with the wide applications of various C-centered radicals adjacent to a heteroatom, however, nitrile-containing alkyl radicals remain largely unexplored. New methods for C(sp3)–H bond oxidative functionalization of alkyl nitriles and new mechanistic manifolds would result in the development of a broad range of novel reactions. Therefore, this review will give an overview of various types of radical cyanoalkylation using the key alkyl nitrile reactants, which lie beyond traditional coupling chemistry.

A facile difluoroalkylation and 1,2-aryl migration reaction commencing from allylic alcohols and simple BrCF2COOEt was developed. This metal-free method offers chemists green and efficient access to important difluoro 1,5-dicarbonyl compounds in moderate to good yields with good functional group tolerance. Sodium hydrosulfite was used as a low-toxic, cheap, environmentally friendly, and efficient radical initiator. The feasibility of performing the transformation on a large scale potentially allows the further application of the present method in other fields.

Herein, we have developed a facile and effective approach for synthesizing a novel kind of porous nitrogen-doped carbon-coated MnO nanosphere. The porous Mn2O3 nanospheres are initially obtained by the calcination treatment of a coordination self-assembled aggregation precursor (referred to as Mn(OAc)2-C-8). Then, MnO@N-doped carbon composites (MnO@NCs) are obtained by the calcination of the Mn2O3 nanospheres coated with polydopamine (Mn2O3@PDA). The MnO@NCs are evaluated as an anode for lithium ion batteries (LIBs), which exhibit high specific capacity, stable cycling performance (1096.6 mA h g−1 after 100 cycles at 100 mA g−1) and high coulombic efficiency (about 99% over 100 cycles). The unique structure design and synergistic effect not only settle the challenges of low conductivity and poor cycling stability of transition metal oxides but also resolve the imperfection of inferior specific capacity of traditional graphite materials. Importantly, it may provide a commendable conception for developing new-fashioned anode materials to improve the lithium storage capability and electrochemical performance.

In this paper, we report a synthetic route for cobalt sulfides nanoparticles embedded in porous carbon fibers (Co9S8@C) by carbonizing polydopamine (PDA)-coated metal coordination polymers (MCPs) and subsequent sulfidation process. This material serves as an anode for lithium-ion batteries, which exhibits high capacity and good rate capability. At a rate of 0.1C, a high reversible capacity of 1565 mA h g−1 is being obtained. In addition, the battery maintains a stable reversible capacities of 606 mA h g−1 for 300 cycles at 1C. The improvement of lithium-storage performance is mainly attributed to the smart design of carbon-wrapped mesoporous Co9S8 fibers, which not only prevents aggregation and volume change of the Co9S8 particles, but also enables good conductivity, and thus enhances electrochemical stability.

Different from the conventional synthesis methods and substrates, we designed a brand new method for synthesizing amides with platinum nanowires as catalysts and tert -butylhydroperoxide (TBHP) as the oxidant. Influence of factors, such as the catalyst, solvents, and the reaction temperature, were studied to determine the optimal reaction conditions. In addition, we explored the substrate generality and observed excellent yields.

A metal-free, visible-light photoredox-catalyzed three-component [3 + 2 + 1] heteroannulation for accessing modular fluoroalkylated pyrimidines from readily available silyl enol ether, amidine, and fluoroalkyl halide is developed. This protocol distinguishes itself by broad functional group tolerance in a regioselective manner, which provides a complement to the existing methods for the construction of pharmaceutically and biologically active organofluorine compounds.

The Pd/TiO2 nanosheets were successfully prepared through a facile chemical reduction method via depositing various amounts of Pd nanoparticles onto TiO2 nanosheets with a high percentage of exposed (001) facets. The chemical and physical properties of the samples were generally investigated using transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV-visible spectra and photoluminescence spectra. The as-prepared Pd/TiO2 nanosheets all showed an immensely improved photocatalytic activity for water splitting compared to pure anatase TiO2 nanosheets, among which, the TiO2 nanosheets decorated with 0.18 at% Pd NPs could provide the highest H2 evolution rate of 3096 μmol g−1 h−1. In short, we had developed a simple method to improve the activity of anatase TiO2 nanosheets with exposed (001) facets in photocatalytic water splitting, which might be one of the potential pathways to modify semiconductor materials in the catalytic field.

A novel type of transition bimetal–organic frameworks was described as a heterogeneous catalyst for the oxidative coupling of amines to imines under mild conditions, which was easily synthesized by the coordination assembly of manganese(II) and cobalt(II) with 1,3,5-benzenetricarboxylic acid (H3BTC) for the first time. The metal–organic framework material was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry and N2 sorption. As an environmentally benign heterogeneous catalyst, the catalytic ability of the metal–organic framework material was then detected to be excellent for the tert-butyl hydroperoxide (TBHP) promoted direct oxidative coupling of benzylamines to imines in excellent yields (up to 100%) in methanol for 3 h. More importantly, it could be recycled up to six runs, while still maintaining its high catalytic activity.

In this study, we describe a rapid and environmentally friendly synthesis of bare Co3O4 nanocrystals derived from Co(ii) oleate complexes by calcination treatment. When directly used as anode materials for lithium-ion batteries (LIBs), the as-prepared nanocrystals could deliver a high reversible capacity of 980 mA h g(-1) after 250 cycles at a current density of 100 mA g(-1) and excellent cycling performance, which may be beneficial to promote the further development of the next generation of lithium ion batteries. The synthetic route can offer great advantages for the flash preparation of other metal oxide nanocrystals for energy storage application.

A novel kind of Co-based metal–organic frameworks (MOFs) are firstly prepared by coordination assembly of Co(II) and 1,3,5-benzenetricarboxylic acid (H3BTC) through a hydrothermal route (referred to as Co-BTC MOF). Such Co-BTC MOF have a zigzag vermicular-like shape with a length of 126 nm and a width of 55 nm. Co-BTC MOFs without calcination treatment are applied as anode materials for lithium-ion batteries (LIBs) and show superior electrochemical performance, including high lithium storage capacity (1739 mA h g−1 in the first discharge process at a current density of 100 mA g−1), excellent coulombic efficiency (above 99% in the 199th cycle) and cycling performance (>750 mA h g−1 over 200 cycles) in the potential range of 0.01–3.0 V vs. Li/Li+. Such excellent electrochemical performance may be derived from the conjugated carboxylate moiety and the linker structure. More importantly, the facile approach may also be extended to other metal-based MOFs and the intriguing results show that nano-sized MOFs will be regarded as futuristic anode materials for advanced lithium storage.

Herein, we have designed graphene-coated porous cobalt oxide fibers (Co3O4@G) using coordination polymers as precursors through calcination followed by a subsequent self-assembly process. The graphene-coated porous cobalt oxide fiber nanostructures not only provide good conductivity, but also prevent the aggregation and volume change of the Co3O4 nanoparticles during lithium storage processes. When serving as anode materials in the lithium-ion batteries, the obtained Co3O4@G composites, exhibit remarkable electrochemical performances, including high specific capacity (∼1303.9 mA h g−1 at a current density of 0.2 A g−1), excellent cycling stability (1153 mA h g−1 retention after 80 cycles at a current density of 0.2 A g−1) and high rate capability.

In this manuscript, we demonstrated a facile route for the controllable design of “Fluorine (F)-doped carbon” (C/F)-treated TiO 2 hollow spheres with mesoporous shells (MHTO-C/F). The fabrication of this distinct mesoporous hollow structures and the C/F coating could effectively improve the electrolyte permeability and architectural stability, as well as electrical conductivity and lithium ion mobility. As anticipated, MHTO-C/F has several remarkable electrochemical properties, such as a high specific reversible capacity of 252 mA h g −1 , outstanding cycling stability of more than 210 mA h g −1 after 100 cycles at 0.5 C, and good rate performance of around 123 mA h g −1 at 5 C (1 C = 168 mA g −1 ). These properties are highly beneficial for lithium storage.

Plentiful tertiary amine derivates are synthesized by direct formation of tertiary amines by the interaction of aldehydes with secondary amines over Pt nanowires under mild conditions. This method offers a green and rapid approach to transform secondary amines into various tertiary amines.

A simple and efficient system for Suzuki cross-coupling reactions was developed using a ligandless catalyst of Pd nanoclusters generated in situ from Pd(acac)2. The cross-coupling reactions proceeded under mild reaction conditions with a high reaction rate (5 min) to give various biaryls in high yields. The system also exhibited catalytic potential for Heck reaction between aryl bromides and styrene.

Bimetallic Pt-based nanodendrites are of particular interest in various catalytic applications due to their high surface areas and low densities. Herein, we provide a facile method for one-pot synthesis of PtRu nanodendrites via the co-reduction of Pt and Ru precursors in oleylamine by H2. The as-fabricated PtRu nanodendrites exhibit superior catalytic activity and durability compared with PtRu nanocrystals (NCs), synthesized under the same reaction conditions, and the commercial Pt/C catalyst towards the methanol oxidation reaction (MOR).

A novel type of transition bimetal–organic frameworks was described as a heterogeneous catalyst for the oxidative coupling of amines to imines under mild conditions, which was easily synthesized by the coordination assembly of manganese(II) and cobalt(II) with 1,3,5-benzenetricarboxylic acid (H3BTC) for the first time. The metal–organic framework material was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry and N2 sorption. As an environmentally benign heterogeneous catalyst, the catalytic ability of the metal–organic framework material was then detected to be excellent for the tert-butyl hydroperoxide (TBHP) promoted direct oxidative coupling of benzylamines to imines in excellent yields (up to 100%) in methanol for 3 h. More importantly, it could be recycled up to six runs, while still maintaining its high catalytic activity.

Plentiful tertiary amine derivates are synthesized by direct formation of tertiary amines by the interaction of aldehydes with secondary amines over Pt nanowires under mild conditions. This method offers a green and rapid approach to transform secondary amines into various tertiary amines.

Bimetallic Pt@Ir zigzag nanocomplexes were successfully synthesized with a uniform morphology via the simple reduction of Ir(acac)3 on the surface of Pt nanorods. The novel Pt@Ir nanocomplexes exhibited good catalytic activity in hydrogenation reactions under mild conditions, such as the hydrogenation of nitroaromatic compounds. The highest yield of the obtained product achieved was ∼99.9% using H2 as the sole reductant.

In this study, we report the design and synthesis of a silver nanowire-γ-Fe2 O3 coaxial nanocable architecture (Ag NWs@γ-Fe2 O3 nanocable) through mild oxidation of [Fe(CO)5 ] on the surface of silver nanowires followed by a calcination process. After optimization of the structural design, the Ag NWs@γ-Fe2 O3 nanocable could deliver superior lithium storage performance in terms of high reversible capacity, good rate performance, and excellent stability, such as a high reversible capacity of about 890 mA h g(-1) after 60 cycles at a current rate of 0.1 C (1.0 C=1005 mA g(-1) ). The reversible capacity remains as high as about 550 mA h g(-1) even at a high current rate of 2.0 C. This dramatic performance is mainly attributed to the smart coaxial design, which can not only alleviate the large volume change and prevent the aggregation of γ-Fe2 O3 nanoparticles, but also enables good conductivity and thus enhances fast charge transfer. The unique structural features of the Ag NWs@γ-Fe2 O3 nanocable represent a promising anode material in lithium-ion battery applications.