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Rhodium complexes coordinated by Chenphos are very effective catalysts for the enantioselective hydrogenation of α-aryloxy- and α-alkoxy-substituted α,β-unsaturated carboxylic acids under mild conditions in CF3CH2OH. The catalytic system could be successfully employed in building the core structure of a new FDA approved drug LCZ 696. [ABSTRACT FROM AUTHOR]

Cyclic voltammograms, UV-visible and FT-IR spectra show that porphyrins with two N-methyl-3-pyridylethynyl substituents can undergo reductive electropolymerization on Pt and ITO electrodes. The films are redox active and a mechanism is suggested [ABSTRACT FROM AUTHOR]

A novel microspherical composite with an Au@SiO2 core and mesoporous aluminosilica shell is synthesized and used as the heterogeneous catalyst in the aerobic epoxidation of cis-cyclooctene, exhibiting great catalytic activity and stability. [ABSTRACT FROM AUTHOR]

The progress of proton exchange membrane fuel cells (PEMFCs) in the clean energy sector is notable for its efficiency and eco-friendliness, although challenges remain in terms of durability, cost and power density. The oxygen reduction reaction (ORR) is a key sluggish process and although current platinum-based catalysts are effective, their high cost and instability is a significant barrier. Single-atom catalysts (SACs) offer an economically viable alternative with comparable catalytic activity for ORR. The primary concern regarding SACs is their operational stability under PEMFCs conditions. In this article, we review current strategies for increasing the catalytic activity of SACs, including increasing active site density, optimizing metal center coordination through heteroatom doping, and engineering porous substrates. To enhance durability, we discuss methods to stabilize metal centers, mitigate the effects of the Fenton reaction, and improve graphitization of the carbon matrix. Future research should apply computational chemistry to predict catalyst properties, develop in situ characterization for real-time active site analysis, explore novel catalysts without the use of platinum-based catalysts to reduce dependence on rare and noble metal, and investigate the long-term stability of catalyst under operating conditions. The aim is to engineer SACs that meet and surpass the performance benchmarks of PEMFCs, contributing to a sustainable energy future. [ABSTRACT FROM AUTHOR]

The document is the contents list for an issue of the journal Chemical Communications. It includes the titles and authors of various articles that will be featured in the issue. Some of the topics covered include PGM-free single atom catalysts, challenges and advances in MOF-based gas separation membranes, and the synthesis and stability of a Ti-DOTA complex. The journal is published by The Royal Society of Chemistry and is dedicated to sustainable chemistry and new solutions. [Extracted from the article]

This work developed an aptamer-dye complex as a label-free ratiometric fluorescence sensor for rapid analysis of THC and its metabolite in sewage samples. Integrated with a portable fluorescence capture device, this sensor exhibited excellent sensitivity with visualization of as low as 0.6 μM THC via naked-eye observation, and THC analysis can be accomplished within 4 min, which would be a complementary tool for quantifying THC in sewage samples to estimate cannabis consumption. [ABSTRACT FROM AUTHOR]

The document is the contents list for the journal "Chemical Communications" published in 2024. It includes a range of articles on various topics such as electrocatalysts for water splitting, photocatalytic water splitting, and chiral photoswitches. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a brief overview of the articles included in the issue. [Extracted from the article]

Herein we present the effect of artificially imposed topological constraint on calmodulin (CaM) backbone dynamics and its molecular recognition behavior. While backbone dynamics of CaM remain largely unperturbed, the thermodynamic profile of CaM binding to the smooth-muscle myosin light-chain kinase (smMLCK) peptide is modulated significantly. [ABSTRACT FROM AUTHOR]

Heterocyclic compounds are widely found in many natural isolates and medicinally relevant compounds, as well as some fine chemicals. The development of general and efficient methods for the construction of heterocyclic compounds is one of the most important tasks in synthetic organic chemistry. Along these lines, [3+m]-cycloaddition reactions involving in situ generated azaoxyallyl cations as the 3-atom units have emerged as a powerful method for the synthesis of nitrogen-containing heterocycles. In this feature article, we highlight recent advances in this rapidly growing area, mainly focusing on the reaction design as well as the reaction mechanism. [ABSTRACT FROM AUTHOR]

Here, we show a designed solid-state nanopore sensor for the direct sensing and quantification of prostate-specific antigen (PSA) as cancer biomarker in serum without any pretreatment. This nanopore technique provides a convenient, fast, and low-cost quantification of cancer biomarkers in clinical samples. [ABSTRACT FROM AUTHOR]

Herein, the unzipping and translocation of DNA duplexes through a sub-2 nm silicon nitride (SiNx) solid-state nanopore have been demonstrated by well-resolved three-level blockades. In order to examine our observations, we applied a simple model which is applicable to the unzipping and translocation processes of DNA duplexes through solid-state nanopores. The generation of these highly recognizable signatures is an important step towards the real applications of solid-state nanopores in complex samples. [ABSTRACT FROM AUTHOR]

A table of contents for the 2016 issue of the journal "Chemical Communications" is presented.

This work proposes a gold nanoparticle (AuNP) based probe to study the single-nanoparticle translocation behavior through a silicon nitride (SiNx) solid-state nanopore. The AuNP probe is functionalized with a rhodamine derivative molecule, termed Rhod-DPA, whose fluorescence can be activated in the presence of Cu2+ due to the binding between Rhod-DPA and Cu2+. The Cu2+ triggered configuration change of Rhod-DPA on the probe surface can induce the plasmon resonance energy transfer (PRET) from single AuNPs to the transformed fluorescent molecules, which can be detected by the color change of AuNP probes under dark-field microscopy (DFM) and their scattering spectra recorded on a spectrometer. By analyzing the peak shifts before and after the addition of Cu2+, evidence of single nanoparticle translocation through the nanopore has been obtained, proving the successful establishment of the tracking strategy. [ABSTRACT FROM AUTHOR]

The table of contents for the January 2014 issue of "Chemical Communications" is presented.

Polypeptides are fascinating materials with unique properties for various biological materials. We highlight here recent advances in amino acid N-carboxyanhydrides (NCAs) and synthetic polypeptides from the aspects of chemistry, self-assembly and biological applications. New synthetic methodologies, mechanistic studies and optimization of polymerization conditions for the preparation of well-defined novel polypeptides are comprehensively reviewed and evaluated. Functional polypeptides, mostly prepared from novel NCA monomers, with ultra-stable helical conformation, stimuli-sensitive properties, or glycoprotein mimetics are summarized. We also highlight a number of interesting self-assembled structures of polypeptides in solid state and solution, with particular emphasis on those structures other than amphiphilic self-assembly. The biological applications of polypeptides in drug and gene delivery are also reviewed. Future directions and perspectives are discussed in the conclusion. [ABSTRACT FROM AUTHOR]

A table of content for the November 10, 2014 issue of the journal "Chemical Communications,"is presented.

A table of contents for the 2013 issue of the periodical "Chemical Communications," is presented.

Light-regulated ion channel-transport across lipid bilayers was realized using structurally simple azobenzene-based amphiphilic small molecules. UV or visible irradiation triggers molecular photoisomerization, which induces structural and membrane affinity changes in self-assembled channels, thus resulting in light-regulated ion transmembrane transport. [ABSTRACT FROM AUTHOR]

The acidic ionic liquid (IL) functionalized polymer (PDVB–SO3H–[C3vim][SO3CF3]) possesses abundant nanoporous structures, strong acid strength and unique capability for deconstruction of crystalline cellulose into sugars in ILs. The polymer shows much improved catalytic activities in comparison with mineral acids, homogeneous acidic ionic liquids and the acidic resins such as Amberlyst 15. The enhanced catalytic activity found in the polymer is attributed to synergistic effects between the strongly acidic group and the ILs grafted onto the polymer, which by itself is capable of breaking down the crystalline structures of cellulose. This study may help develop cost-effective and green routes for conversion of biomass to fuels. [ABSTRACT FROM AUTHOR]