Porous organic polymers (POPs), a class of highly crosslinked amorphous polymers possessing nano-pores, have recently emerged as a versatile platform for the deployment of catalysts. The bottom-up approach for porous organic polymer synthesis provides the opportunity for the design of polymer frameworks with various functionalities, for their use as catalysts or ligands. This tutorial review focuses on the framework structures and functionalities of catalytic POPs. Their structural design, functional framework synthesis and catalytic reactions are discussed along with some of the challenges.

Activate and reduce: Carbon dioxide was reduced with silane using a stable N-heterocyclic carbene organocatalyst to provide methanol under very mild conditions. Dry air can serve as the feedstock, and the organocatalyst is much more efficient than transition-metal catalysts for this reaction. This approach offers a very promising protocol for chemical CO(2) activation and fixation.

The use of carbon dioxide as a renewable and environmentally friendly source of carbon is highly attractive. This article focuses on recent developments in important new reactions and new catalysts for homogeneous CO(2) transformations under mild reaction conditions. Other than traditional organometallic catalysts, organocatalysts have also been applied in the chemical conversion of CO(2) and have demonstrated very promising ability in this field. As the coupling of epoxides with CO(2) to form cyclic carbonates or polycarbonates has been well documented, it will be excluded from this article.

Imidazolium salts, distinct from their parent imidazoles, are made up of a discrete cation and anion pair, and have found widespread utility as ionic liquids. A lesser known function of such imidazolium salts includes the application of these salts in biological systems, and several areas of bio-applications, including antitumour, antimicrobial, antioxidant and bioengineering applications, will be presented and discussed in this review. The wide-ranging applications and versatility of these imidazolium salts stem from the ease of their structural variation, in which properties such as amphiphilicity, lipophilicity and solubility can be tuned.

Porous redox-active metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) have emerged as electrode materials for energy storage devices. These porous frameworks have different levels of intrinsic properties such as low solubility, high ionic conductivity (porosity) and low electrical conductivity, all of which are critical parameters when utilised as electrode materials. This Minireview focuses on recent developments of using porous MOFs/COFs as redox active electrode materials for energy storage and strategies to improve their electrochemical performance.

Carbon dioxide is attractive as a renewable carbon source and an environmentally friendly chemical reagent. [1][2][3][4] Significant efforts have been devoted towards exploring technologies for CO 2 transformation, whereby metal catalysts play a key role. [5][6][7][8][9][10] N-heterocyclic carbenes (NHCs) are well established as organocatalysts and ligands in organic synthesis. [11][12][13][14] With their lone pair of carbene electrons, NHCs behave as nucleophiles. It has been known that nucleophilic NHCs can activate CO 2 to form imidazolium carboxylates. [15,16] However, the application of such carboxylates has been limited to the preparation of precursors to NHC-metal complexes and halogen-free ionic liquids, and some stoichiometric transcarboxylation reactions. [17][18][19][20] The release of CO 2 from the imidazolium carboxylates and the completion of a catalytic cycle with NHCs may lead to a new and exciting metal-free protocol for CO 2 transformation. In this work, we envision the use of a hydrosilane in the reaction as a hydride donor to the activated carbon dioxide, reducing CO 2 ultimately to methoxide (Scheme 1).Catalytic reduction of CO 2 with hydrosilane would proceed exothermically and could facilitate utilization of CO 2 . The development of highly active and robust catalysts for such a reaction remains a major scientific challenge. In previous reports of the addition of hydrosilane to CO 2 , active transition-metal complexes served as catalysts. Ruthenium and iridium complexes were first reported in the early 1980s as catalysts for the hydrosilylation of CO 2 . [21,22] More recently, Pitter and co-workers described the hydrosilylation of CO 2 catalyzed by ruthenium-acetonitrile complexes, yielding formoxysilanes. [23][24][25] Matsuo and Kawaguchi reported the homogeneous reduction of CO 2 with hydrosilanes catalyzed by zirconium-borane complexes, yielding methane. [26] The practicality of applications of these different systems was limited by their sensitivity to air and moisture, as well as the low activities of the organometallic catalysts. Herein we describe the first hydrosilylation of CO 2 using an organocatalyst. Stable NHC catalysts mediated the effective conversion of CO 2 to methanol under very mild conditions and allowed the use of air as a feedstock.In a typical reaction 1,3-bis(2,4,6-trimethylphenyl)imidazolium carboxylate (Imes-CO 2 , 1; 0.1 mmol) [15] was dissolved in N,N-dimethylformamide (DMF, 2 mL) in a vial, and CO 2 was introduced with a balloon. Diphenylsilane (1 mmol) was introduced to the vial, and the reaction mixture was stirred at room temperature. The reaction was monitored by gas chromatography/mass spectrometry (GC-MS). It was found that diphenylsilane was fully consumed in 6 h. The expected formoxysilane product occurred as a minor product in the early stages of the reaction and disappeared as the reaction progressed. Further studies showed that the reaction intermediates, diphenyldiformoxysilane (Ph 2 Si(OCHO) 2 , 2) and diphenylformoxysilane (Ph 2 SiH(OCHO), 3), were...

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This article focuses on the recent development of new strategies and approaches for improving the performance of organic electrodes for rechargeable lithium (sodium) batteries.