Late‐stage Ligand Modification After Coordination Strengthens Stereoselectively Self‐Assembled Hemiaminal Ether Complexes

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Late-stage Ligand Modification After Coordination Strengthens Stereoselectively Self-Assembled Hemiaminal Ether Complexes

Fragile hemiaminal ether linkages present in the backbone of koneramine ligands bound to copper(II) in stereoselectively self-assembled complexes were transformed into sturdy methylene linkages by late-stage ligand modification after coordination with the retention of coordination sphere.


Abstract

Fragile hemiaminal ether linkages present in the backbone of koneramines (LROR’), tridentate ligands, bound to copper(II) in stereoselectively self-assembled syn-[Cu(LROR’)X2] complexes were transformed into sturdy methylene linkages to make corresponding rac-[Cu(LRH)Cl2] complexes by late-stage ligand modification after coordination with the retention of coordination sphere. The generality of stereoselective self-assembly of koneramine complexes is shown by utilising a number of metal ions, anions, amines, alcohols and thiols with complete characterisations.

Covalent Organic Framework‐based Solid‐State Electrolytes, Electrode Materials, and Separators for Lithium‐ion Batteries

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The increasing global energy consumption has led to the rapid development of renewable energy storage technologies. Lithium-ion batteries (LIBs) have been extensively studied and utilized for reliable, efficient, and sustainable energy storage. Nevertheless, designing new materials for LIB applications with high capacity and long-term stability is highly desired but remains a challenging task. Recently, covalent organic frameworks (COFs) have emerged as superior candidates for LIB applications due to their high porosity, well-defined pores, highly customizable structure, and tunable functionalities. These merits enable the preparation of tailored COFs with predesigned redox-active moieties and suitable porous channels that can improve the lithium-ion storage and transportation. This review summarizes the recent progress in the development of COFs and their composites for a variety of LIB applications, including (quasi) solid-state electrolytes, electrode materials, and separators. Finally, the challenges and potential future directions of employing COFs for LIBs are also discussed, further promoting the foundation of this class of exciting materials for future advances in energy-related applications.

Synthetic Routes to Imidates and Their Applications in Organic Transformation: Recent Progress

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Synthetic Routes to Imidates and Their Applications in Organic Transformation: Recent Progress

Imidates are important organic intermediates used in several synthetic transformations towards N-heterocycles, natural products and metal complexes with a potential catalytic effect. Herein, the recent synthetic approaches and diverse applications of imidates were categorized and summarized. A wide range of organic compounds, mainly nitriles, isocyanides, amides, imines, and alkynes are used as starting materials. This review also summarizes the latest synthetic approaches to imidates that have been developed the recent years and some of their significant applications in the field of organic synthesis.


Abstract

Recent synthetic approaches and diverse applications of imidates are presented in this review. These motifs are successfully used as intermediates in organic transformations, such as the synthesis of N-heterocycles, natural products and metal complexes with a potential catalytic effect. Consequently, many attempts have been made for the development of efficient and facile synthetic methods of imidates in the past few years, as a continuum of previous paths. A wide range of organic compounds can be used as starting materials for these syntheses, including nitriles, isocyanides, amides etc. which through simple and flexible processes are converted to the desired imidates. Herein, an exploration of the recent synthetic routes of imidates and their diverse applications in organic transformations has been categorized and summarized.

CuBO2: a potential alternative for NiO as a hole acceptor layer

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P-type metal oxides, and in particular NiO, are typically used as hole accepting layers in dye-sensitized photocathodes. Delafossites (CuMO2) with M=B, Al, Cr or Ga have recently been proposed as attractive substitutes for NiO, with theoretically a higher hole mobility than NiO, and therefore allowing a higher efficiency when the photocathode is applied in solar to fuel devices. We have experimentally validated the photoelectrochemical performance of photocathodes consisting of nanoporous CuBO2 (CBO) on Fluorine-doped Tin Oxide substrates, photosensitized with a light absorbing P1 dye. Femtosecond transient absorption and time-resolved photoluminescence studies show that light-induced hole injection occurs from the P1 dye into the CBO in a few ps, comparable to the time constant observed for NiO-based photocathodes. Importantly, the CBO-based photocathode shows significantly slower charge recombination than the NiO-based analogue. These results illustrate the promise of CBO as a p-type semiconductor in solar energy conversion devices.

Trans‐N‐alkylation Covalent Exchanges on 1,3,4‐Trisubstituted 1,2,3‐Triazolium Iodides

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1,3,4-Trisubstituted 1,2,3-triazolium salts having either aliphatic or benzylic substituents at the N-1 and N-3 positions were synthesized in two steps involving: i) copper(I) catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC), and ii)N-alkylation of the 1,2,3-triazole intermediates. Trans-N-alkylation reactions in bulk and in the presence of excess methyl iodide were monitored by 1H NMR spectroscopy for each 1,2,3-triazolium molecular model. By assigning the different formed species and their respective evolution with time, it was possible to conclude that trans-N-alkylation exchange reactions are significantly faster for benzylic substituents than for aliphatic ones. Furthermore, the exchange reactions are noticeably faster at the N-3 position than at the N-1 position most likely due to the steric hindrance induced by the neighboring C-4 substituent. The kinetics of trans-N-alkylation reactions are thus influenced by both the chemical nature of the N-1 and N-3 substituents and the regiochemistry of the 1,2,3-triazolium group. This provides important structural design rules to improve the properties of thermosetting covalent adaptable networks involving trans-N-alkylation of 1,2,3-triazolium salts.

Design, Synthesis of Novel 1,2,3‐Triazole Pendent Quinazolinones and their Cytotoxicity Against MCF‐7 Cell Line

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A library of 6-(((1-(substitutedphenyl)-1H-1,2,3-triazol-4-yl)methyl)amino)-3-methylquinazolin-4(3H)-one analogues synthesized from Isatin precursor through a series of nitration, reduction, hydrolysis, cyclization and click reaction. The structures of compounds were characterized by spectral data including IR, 1H NMR, 13C NMR and Mass. The novel quinazolinone – 1,2,3-triazoles were screened for their cytotoxicity against the human breast adenocarcinoma cell lines MCF-7 by MTT assay. 4-Isopropyl and 2-bromo substituted analogues executed high activity against MCF-7 cell line with IC50 value of 10.16±0.07 µM and 11.23±0.20 µM compared to the Doxorubicin whose IC50 value is 10.81±0.03 µM. The activity of remaining compounds is good to moderate. Further, the molecular docking studies against the crystal structure of Epidermal Growth Factor Receptor delivered the best binding energies and the interactions such as H-bond and hydrophobic are inevitable. The predicted pharmacokinetic properties results showed that these compounds have more drug likeness properties.

Covalent Triazine Framework Nanosheets: Synthesis and Energy Conversion and Storage

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Comprehensive Summary

Covalent triazine framework nanosheets (CTF NSs), an emerging class of two-dimensional nanomaterials, have received great attention due to their abundant active sites, permanent porosity, molecular structural diversity, superior chemical/thermal stability, and short charge diffusion path, enabling technological breakthroughs in a myriad of applications. The forefront developments and applications of CTF NSs as photocatalysts and electrochemical electrodes have conferred superior performance and made great impact in the field of energy and advanced catalysis. This forward-looking review aims to summarize the research trends, synthesis, properties of CTF NSs and their CTF counterpart, and highlight their progress in applications with respect to energy storage and conversion devices. Finally, the current challenges and future perspectives for CTF NSs are also presented.

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Gel biopolymer electrolytes based on saline water and seaweed to support the large‐scale production of sustainable supercapacitors

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Climate change and the demand for clean energy have challenged scientists worldwide to produce/store more energy to reduce carbon emissions. This work proposes a conductive gel biopolymer electrolyte to support the sustainable development of high-power aqueous supercapacitors. The gel uses saline water and seaweed as sustainable resources. Herein, a biopolymer agar‒agar, extracted from red algae, is modified to increase gel viscosity up to 17-fold. This occurs due to alkaline treatment and an increase in the concentration of the agar‒agar biopolymer, resulting in a strengthened gel with cohesive superfibres. The thermal degradation and agar modification mechanisms are explored. The electrolyte is applied to manufacture sustainable and flexible supercapacitors with satisfactory energy density (0.764 W h kg-1) and power density (230 W kg-1). As an electrolyte, the aqueous gel promotes a long device cycle life (3500 cycles) for 1 Ag-1, showing good transport properties and low cost of acquisition and enabling the supercapacitor to be manufactured outside a glove box. These features decrease the cost of production and favor scale-up. To this end, this work provides eco-friendly electrolytes for the next generation of flexible energy storage devices.

Recent progress in all‐solution‐processed organic solar cells

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Comprehensive Summary

All-solution-processed organic solar cells (OSCs) (from the bottom electrode to the top electrode) are highly attractive thanks to their low cost, lightweight and high-throughput production. However, achieving highly efficient all-solution-processed OSCs remains a significant challenge. One of the key issues is the lack of high-quality solution-processed electrode systems that can replace indium tin oxide (ITO) and vacuum-deposited metal electrodes. In this paper, we comprehensively review recent advances in all-solution-processed OSCs, and classified the devices as the top electrode materials, including silver nanowires (AgNWs), conducting polymers and composite conducting materials. The correlation between electrode materials, properties of electrodes, and device performance in all-solution-processed OSCs is elucidated. In addition, the critical roles of the active layer and interface layer are also discussed. Finally, the prospects and challenges of all-solution-processed OSCs are presented.

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