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A highly reversible Zn metal anode is the prerequisite for realizing the practical applications of aqueous Zn ion batteries (ZIBs), which are limited by severe zinc dendrites and corrosion. Herein, bio-inspired hydroxyl-rich L-ascorbic acid (vitamin C, L-Aa) was employed to regulate coordination chemistry via the strong interaction between –OH and H2O with dual remodeling functions and further improve the reversibility of Zn anodes. Specifically, L-Aa not only reconstructs the Zn2+ solvation shell, thus reducing Zn2+ desolvation energy, but also forms a molecular adsorption interface via excellent zincophilicity to improve zinc redox kinetics and suppress Zn anode corrosion. Meanwhile, the molecular adsorption interface facilitates the homogenization of the interfacial electric field, thereby promoting the predominant deposition of Zn(002). Consequently, the Zn//Cu asymmetric cell presents a low overpotential for zinc nucleation and exceptional average coulombic efficiency (CE) of 99.6% over 1200 cycles at a high current density of 20 mA cm−2. The Zn//Zn cell also delivers excellent cycling stability for over 1400 h at 5 mA cm−2. In addition, the Zn//MnO2 full cell exhibits a robust long-term cycling performance of 1000 cycles at 1 A g−1. This strategy of simultaneously regulating coordination chemistry and further constructing molecular interfaces may boost the applications of highly reversible ZIBs. [ABSTRACT FROM AUTHOR]

In 2011, Zhang's research team, in cooperation with Li and Liu, reported the Pt1/FeOx atomically dispersed catalysts for the first time in the world, and based on this, proposed the concept of "single-atom catalysts". Single-atom catalysts (SACs) have a wide range of industrial application prospects in the catalytic synthesis of fine chemicals due to their high atomic utilization rate and special catalytic activity. With the deepening of the research, the preparation methods of SACs emerge in an endless stream, but it is still an urgent problem to realize the industrial production of highly stable SACs prepared in small batches (gram level) or even in large batches (kilogram level). In this review paper, several typical solvent-free green synthetic strategies (e.g., ball milling, physical mixing, gas migration, and pyrolyzing coordination polymers (including MOFs)) for the batch preparation of SACs are introduced. And typical catalytic application of SACs in green synthesis of fine chemicals by means of oxidation reaction, hydrogenation reaction, coupling reaction and other reactions are also introduced. This is the first review paper focusing on the mass preparation techniques of SACs and their applications in fine chemicals production. [ABSTRACT FROM AUTHOR]

Nonisocyanate polyurethanes (NIPUs) are an emerging class of polyurethanes produced by circumventing the use of hazardous isocyanates and phosgene in their synthetic routes. In this study, we introduce a novel class of water-soluble/dispersible nonisocyanate polyurethanes (NIPUs) containing phosphate pendant groups, referred to as NIPU phosphate monoesters, by applying green chemistry principles. Linear NIPU polymers with number average molecular weight (Mn) values ranging between 7400 and 13 600 Da and weight average molecular weight (Mw) values between 13 900 and 27 800 Da were synthesised by the polymerization of bio-derived cyclic biscarbonates 4,4′-(((furan-2,5-diylbis(methylene)) bis(oxy))bis(methylene)) bis(1,3-dioxolan-2-one) (FuBCC) and bis((2-oxo-1,3-dioxolan-4-yl)methyl) succinate (SuBCC) with 1,5-pentanediamine (cadaverine) by utilizing green solvents. Subsequent functionalization of the resultant NIPUs via mild and selective phosphorylation using tetrabutylammonium dihydrogenphosphate (TBAP) as a phosphate source delivered NIPU phosphate monoesters containing up to 50% phosphate functionality as determined by 1H NMR. Interestingly, these phosphate-containing NIPUs were soluble/dispersible in water without the need for any external surfactants/co-solvents and demonstrated inherent aerobic biodegradability (56–75% in 28 days). Furthermore, the NIPU phosphate monoesters exhibited remarkable biocompatibility, showing slight to no growth inhibition of human keratinocyte HaCaT cells at concentrations up to 1 mg mL−1. In vitro skin irritation assays on reconstructed human epidermis confirmed their non-skin irritant properties. These NIPU phosphate monoesters also exhibited multifunctional characteristics including oil-in-water emulsion stabilization ability and antimicrobial activity. This work emphasizes the scope and potential of these bio-derived, non-toxic and biodegradable nonisocyanate polyurethane phosphate monoesters as multifunctional additives in personal care/cosmetic applications. [ABSTRACT FROM AUTHOR]

The separation of C2H2/C2H4 is a challenging task, and adsorptive separation based on porous materials offers a promising energy-efficient alternative. Porous coordination polymers (PCPs) have been advocated as potential adsorbents with high separation performance (adsorption capacity and selectivity) by precisely tuning their pore size and chemistry. However, to achieve the goal of green chemistry and pioneer PCPs for practical applications, not only the separation performance but also low regeneration energy and synthetic cost are crucial factors. We herein prepared a novel PCP TJE-1 with rational distribution of cooperative supramolecular interaction sites, exhibiting a very high C2H2 uptake of 5.27 mmol g−1, and a C2H2 selective adsorption over C2H4 under 1 bar, at 298 K. Theoretical calculations indicate that the selectivity originates from the difference in hydrogen bonding and π interactions, resulting in a low isosteric heat of adsorption for C2H2 (35.5 kJ mol−1). Moreover, TJE-1 also remains stable in aqueous acid/base solutions and can be synthesized with scaling up using economical precursors (about $1.45 per g and $0.13 per g for two ligands). This strategy offers guidance on the development of next-generation PCPs with integrated performance that is highly beneficial for industrial gas separations. [ABSTRACT FROM AUTHOR]

Hydroaminomethylation (HAM) of olefins constitutes one of the most promising and practical methods to produce amines, but control of the selectivity between linear and branched products is still challenging. Herein, a series of solid main-chain NHC–rhodium(I) polymers prepared by coordination assembly were found to be highly efficient single-site catalysts in the HAM of olefins. A dramatic enhancement of both productivity (up to 98% yield) and linear selectivity (up to 99 : 1) was observed, largely due to the constraints imposed by the extended coordination assembly structure of the solid catalysts. As well as the broad substrate scope, a record turnover number of 2.1 × 105 was achieved, and the solid catalyst could be reused more than 18 times without obvious loss of activity and selectivity. The protocol has a high tolerance of sensitive functional groups, and its utility was exemplified by the synthesis of several leading pharmaceuticals directly from allyl alcohols or heterocyclic amines without any protection or deprotection operations, and at a scale of up to one gram. [ABSTRACT FROM AUTHOR]

Ligands play a key role in modern catalysis research and occasionally determine whether a reaction will take place under specific conditions, such as in water. In this experiment, ligands containing an indole-based diacid moiety were employed to prepare the corresponding cobalt coordination polymer material (Co-CIA) and porous oval polymer material (Co-NCIA). Interestingly, it was observed that Co-CIA could promote the alkylation of ketones with alcohols and alcohols with alcohols, while Co-NCIA was effective for the synthesis of 1-benzyl-2-aryl-1H-benzo[d]imidazoles from various phenylenediamine and benzyl alcohols through borrowing hydrogen and dehydrogenation strategies. Other mechanism explorations, such as deuterium labeling experiments and a kinetics study, were conducted to better understand Co-CIA and Co-NCIA systems and the related transformations. Our studies provided an efficient method for the development of highly active cobalt coordination polymer materials with excellent recovery performance for dehydrogenation and borrowing hydrogen reactions under water and base-free conditions. [ABSTRACT FROM AUTHOR]

Scaling up the synthesis of metal organic frameworks (MOFs) is necessary in order to demonstrate their potential in industrial applications. This requires the development of a cost efficient and environmentally friendly synthesis protocol which necessitates the understanding of the reaction mechanism, especially for more complex binary ligand MOF systems. Herein, we demonstrate the upscale synthesis (≥100 g) of CPL-1[Cu2(pzdc)2(pz)] n using water as the solvent. The MOF is a binary ligand system composed of 2D layers of copper (Cu(II)) coordinated to 2,3-pyrazinedicarboxylate (pzdc2−) connected by pyrazine pillars (pz). The reaction conditions were investigated and found to be optimal when using the minimum amount of reagent possible in water by adjusting the pH to 6.4 leading to CPL-1 formation with high yield (95% yields) and space–time yield (660 kg m−3 day−1). In addition, the upscaled MOF exhibited similar sorption and separation capacity to the lab scaled one. [ABSTRACT FROM AUTHOR]

An amphiphilic tri-functional ligand (L1) containing a Lewis acidic phosphonium cation, a phosphino-fragment and a hydrophilic sulfonate anion (–SO3−) enabled Pd(OAc)2 to efficiently co-catalyze the hydroxycarbonylation of terminal alkynes towards α,β-unsaturated carboxylic acids. These incorporated functional groups synergistically promoted the reaction, which proved more effective than the ligands lacking –SO3− and/or phosphonium and the mechanical mixtures of the individual functional groups independently. The molecular structure of Pd-L1 indicated that –SO3− in L1 served as a secondary O-donor ligand with reversible coordinating ability, cooperating with the phosphino-fragment to stabilize the Pd-catalyst. The in situ FT-IR analysis verified that the formation and stability of Pd–H active species in charge of hydroxycarbonylation were dramatically facilitated by the presence of L1. It was believed that, over the L1-based Pd-catalyst, H2O was cooperatively activated by the Lewis acidic phosphonium via "acid–base pair" interaction (H2O → P(V)+) and by the hydrophilic SO3−via hydrogen bonding (SO3−⋯H2O), giving rise to the formation of dimeric and mono-nuclear Pd–H species driven by reversible SO3−-coordination. In addition, the L1-based Pd-catalyst could be immobilized in the ionic liquid [Bmim]NTf2 for six-run recycling uses without obvious activity loss and detectable metal leaching. [ABSTRACT FROM AUTHOR]

An environmentally friendly method to prepare new-generation green primary explosives with excellent performances has been developed on the basis of a coordination chemistry strategy. In the present work, constructing energetic coordination polymers (ECPs) based on tetrazole oxide 1H,1′H-[5,5′-bitetrazole]-1,1′-diol (H2BTO) with non-heavy metal cations Mn(ii), Co(ii), Ni(ii), Cu(ii), and Zn(ii) led to five novel green primary explosives without metal ion and organic pollution. Systematic research is conducted to prove these green ECPs as a novel class of lead-free primary explosives. For example, a thermal stability experiment shows that their thermal decomposition temperatures are all beyond 200 °C, while the thermal-resistance experiment demonstrates that compounds 1 and 5 can maintain long-term stability under 100 °C. And the results based on sensitivity tests and detonation parameter simulation reveal that all these compounds possess excellent detonation and safety properties, far outperforming classical primary explosives such as lead azide. Moreover, a modified Koenen test has been conducted to characterize the explosion capacity of these ECPs and by this method compounds 1, 2, 3, and 5 were demonstrated with fast deflagration-to-detonation transition ability. [ABSTRACT FROM AUTHOR]

The in air catalytic hydroboration of ketones and aldehydes with pinacolborane by an iron(ii) coordination polymer (CP) is carried out under mild and solvent-free conditions. The precatalyst is highly active towards a wide range of substrates including functionalized ketones and aldehydes in the presence of KOtBu as an activator, achieving a high turnover number (TON) of up to 9500. Excellent chemoselectivity to aldehydes over ketones was also revealed, which is in sharp contrast with the results obtained under inert atmosphere using the same catalyst system. This catalyst observed here is not only highly efficient but also recyclable for reuse for at least 5 times without losing its effectiveness. [ABSTRACT FROM AUTHOR]

Considering the increasing heavy energy demands and severe environmental issues, researchers have been searching for an alternative renewable source of energy, aiming to achieve carbon neutralization. Biodiesel, which is deemed as an environment-friendly, sustainable, and renewable energy, has attracted extensive concerns worldwide with the merits of non-toxicity, biodegradability, and carbon-neutral nature. Generally, biodiesel is mainly produced via the transesterification of triglycerides and esterification of fatty acids with the assistance of highly effective catalytic material, which is determined to be a critical issue for biodiesel production. Benefiting from the superiorities of huge porosity, uniform pore size, controllable functional group, and excellent activity with stability, organic–inorganic hybrid porous coordination polymers (OIHPCPs) are considered to be promising catalysts for biodiesel production. However, limited reviews have concentrated on the specific application of OIHPCP-based catalytic materials for the production of biodiesel. With this, this study systematically reviews the current application of OIHPCPs in catalyzing the trans/esterification of liquid biomass for biodiesel production, including pristine metal–organic frameworks (MOFs), functionalized MOFs (i.e., acid, base, bifunctional, and enzymatic), MOF derivates, unconventional MOFs (UMOFs), and biomass derivate coordination polymers catalysts. Besides, the important impacts of trans/esterification parameters, such as the amount of catalyst, type and molar ratio of alcohol, reaction temperature and time, water and fatty acids content of the substrate, and auxiliary production technology of biodiesel are also comprehensively evaluated. Finally, the corresponding plausible reaction mechanisms and main conclusions together with future perspectives for OIHPCP applications in biodiesel production are further emphasized. This review is timely and conducive for advancing the bioenergy realms and achieving carbon neutrality. [ABSTRACT FROM AUTHOR]

We present a systematic study of a mild approach for the activation of metal oxides, involving reactivity and self-assembly in the solid state, which enables their solvent-free chemical separation and direct solvent-free and low-energy conversion into coordination polymers and open metal-organic frameworks (MOFs). The approach is inspired by geological biomineralization processes known as mineral weathering, in which long-term exposure of oxide or sulfide minerals to molecules of biological origin leads to their conversion into simple coordination polymers. This proof-of-principle study shows how mineral neogenesis can be mimicked in the laboratory to provide coordination polymers directly from metal oxides without a significant input of either thermal or mechanical energy, or solvents. We show that such "aging" is accelerated by increased humidity, a mild temperature increase and/or brief mechanical activation, enabling the transformation of a variety of high-melting (800 °C-2800 °C) transition (MnII, CoII, NiII, CuII, and Zn) and main group (Mg and PbII) oxides at or near room temperature. Accelerated aging reactions are readily scaled to at least 10 grams and can be templated for the synthesis of two-dimensional and three-dimensional anionic frameworks of Zn, Ni(II) and Co(II). Finally, we demonstrate how this biomineralization- inspired approach provides an unprecedented opportunity for solvent-free chemical segregation of base metals, such as Cu, Zn and Pb, in their oxide form under mild conditions. [ABSTRACT FROM AUTHOR]

Among four different 2-D polymeric silver(i)–bpfb assemblies synthesized, [Ag(μ-bpfb)(N3)]n (4c) having an azide anion was shown to be the best catalyst for the partial oxidation of primary amines to N-monoalkylhydroxylamines with urea hydrogen peroxide (UHP). The method has supplied the minimum E-Factor (which is in the range for bulk chemicals) amongst all of the presented methods. More importantly, the catalyst could be easily recovered and reused for six reaction cycles without any loss of activity. [ABSTRACT FROM AUTHOR]

Efficient and greener synthesis of unsymmetrical organic carbonates is of great importance. In this work, two organotin-oxometalates, Bu2SnMoO4 and (Bu3Sn)2MoO4, were prepared and their catalytic performance for the transesterification of diethyl carbonate (DEC) with alcohols to synthesize unsymmetrical organic carbonates was studied. It was found that (Bu3Sn)2MoO4 was very active and selective for the transesterification of DEC and various alcohols, including alkyl, cyclic, and aryl alcohols due to the synergetic effect between the groups of [MoO4]2− and [Bu3Sn]+ in the catalyst. The yields of the corresponding carbonates could reach 98% at the suitable conditions. The catalyst was reused five times and the activity and selectivity were not changed. We believe that the highly efficient, versatile, greener, inexpensive, selective and stable catalyst has great potential applications in the synthesis of various unsymmetrical organic carbonates from DEC and alcohols. [ABSTRACT FROM AUTHOR]