Site‐selective functionalization of C−H bonds in small complex molecules is a long‐standing challenge in organic chemistry. Herein, we report a broadly applicable and site‐selective aromatic C−H ...dibenzothiophenylation reaction. The conceptual advantage of this transformation is further demonstrated through the two‐step C−H 18Ffluorination of a series of marketed small‐molecule drugs.
A broadly applicable and site‐selective late‐stage aromatic 18Ffluorination reaction is reported. A collection of three electronically different dibenzothiophenes enables 18F labeling of a series of small complex molecules.
Magnetic nanoparticles have attracted significant attention due to their exceptional features and versatile applications, including water and/or wastewater treatment. Discharge of heavy metals and ...other contaminants into water resources is a concern due to the detrimental effects on humans and the environment. Grafting magnetic nanoparticles with amino functional groups yields aminated or amino-functionalized magnetic nanoparticles, which show better results than bare magnetic nanoparticles in water treatment applications. Their magnetic nature is crucial for cost-effective and greener pollutant removal from water since they are magnetically separated and reused without a major change in structure and efficiency. In this review, the synthesis, separation and adsorption processes, and future perspectives for amino-functionalized magnetic nanoparticles are discussed in addition to their applicability in water treatment. Several important works have also been discussed for the removal of metals, radionuclides, organic contaminants, dyes and pathogens from water. The influence of parameters, such as magnetic nanoparticle dosage, pH, contact time, ion selectivity, and recyclability are also presented.
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•Amino-functionalized magnetic nanoparticles (MNPs) for water treatment were discussed.•Recent advances in the fabrication of amino-functionalized MNPs were reviewed.•Removal of metals, radionuclides, organic contaminants and pathogens from water.•Insightful discussion on existing challenges and future developments.
In this work, phosphorylated cellulosic fibers were functionalized with an aminosilane ((3-aminopropyl)triethoxysilane, APTES) using a simple and economical method. Several characterization were ...performed to determine the types of bonds between phosphorylated fibers and grafted APTES. The thermal behavior, hydrophobicity and surface charge variation as a function of pH of the multifunctional cellulose fibers were determined.
Results demonstrate that APTES should proceed through Si-O-C, and possibly Si-O-P, covalent bonds with cellulose although the dimerization of silane through Si-O-Si bonds has also been observed. The terminal amino groups are expected to be partially involved in hydrogen bonds with phosphate hydroxyl groups found at phosphorylated cellulose fiber surface, causing a pulling in the configuration of the grafted APTES. The two chemical modifications proposed in this work do not significantly modify the morphology of cellulose fibers. XRD analysis also shows that the crystal structure of the phosphorylated fibers did not change after functionalization with APTES. The silylated phosphorylated fibers show potential flame-retardant properties with improved hydrophobicity. Furthermore, the functionalization of phosphorylated fibers with APTES changes the pH of zero charge point from 3.2 to 9.4 and providing a zwitterionic structure suitable for the simultaneous adsorption of both cationic and anionic species.
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This paper reviews recent developments in the preparation, surface functionalization, and applications of Fe3O4 magnetic nanoparticles. Especially, it includes preparation methods (such as ...electrodeposition, polyol methods, etc.), organic materials (such as polymers, small molecules, surfactants, biomolecules, etc.) or inorganic materials (such as silica, metals, and metal oxidation/sulfide, functionalized coating of carbon surface, graphene, etc.) and its applications (such as magnetic separation, protein fixation, magnetic catalyst, environmental treatment, medical research, etc.). In the end, some existing challenges and possible future trends in the field were discussed.
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•Comprehensive summary of the main aspects of Fe3O4 magnetic nanoparticles related to their preparation and application.•Classification and intrinsic properties of Fe3O4 magnetic nanoparticles were studied.•Perspectives for the future developments of Fe3O4 magnetic nanoparticles were proposed.
Carbon nanotubes (CNTs) have been widely studied and used for the construction of electrochemical biosensors owing to their small size, cylindrical shape, large surface-to-volume ratio, high ...conductivity and good biocompatibility. In electrochemical biosensors, CNTs serve a dual purpose: they act as immobilization support for biomolecules as well as provide the necessary electrical conductivity for electrochemical transduction. The ability of a recognition molecule to detect the analyte is highly dependent on the type of immobilization used for the attachment of the biomolecule to the CNT surface, a process also known as biofunctionalization. A variety of biofunctionalization methods have been studied and reported including physical adsorption, covalent cross-linking, polymer encapsulation etc. Each method carries its own advantages and limitations. In this review we provide a comprehensive review of non-covalent functionalization of carbon nanotubes with a variety of biomolecules for the development of electrochemical biosensors. This method of immobilization is increasingly being used in bioelectrode development using enzymes for biosensor and biofuel cell applications.
An efficient approach to patterning 2D MoS2 through covalent functionalization of electron beam lithography (EBL)‐defined guiding patterns has been demonstrated by A. Hirsch et al. in their ...Communication (DOI: 10.1002/chem.202102021). This approach opens a convenient avenue for spatially designing and engineering MoS2 nanostructures, and would benefit further exploration of MoS2‐based devices and facilitate efficient manufacture.
Ordered thiol-functionalized microporous silica with BET surface area 1136.64 m(2)/g and high thiol group density was prepared by co-condensation of 3-mercaptopropyltrimethoxysilane and ...tetramethoxysilane in the hydroalcoholic medium with cetyltrimethylammonium bromide. These samples were characterized through BET analysis, XRD, TEM, IR and Raman spectroscopy, (29)Si NMR and elemental analysis. The sorption behaviors and mechanisms of Pb(2+) and Cd(2+) on the samples were studied. The maximum sorption amounts of Pb(2+) and Cd(2+) were 130 and 39 mg/g, respectively. Freundlich isotherm was proved to describe the sorption data better than Langmuir isotherm and pseudo second order kinetic model could fit the sorption kinetic processes well. The pH and electrolyte NaNO(3) influenced the sorption of Pb(2+) and Cd(2+) on the samples significantly. According to hard and soft acids and bases theory and the information analyzed from XPS, the sorption mechanisms could be explained as primary chemical adsorption and secondary physical adsorption.
Robust, reliable, and quantitative detection of biomarkers at ultra-low concentration is of great importance in clinical settings. Biosensor, an analytical device used for sensitive and selective ...detection of biomarkers offers various advantages over the conventional clinical diagnosis, which is both time consuming and not suitable for point of care/onsite diagnosis. A revolution in the understanding and synthesis of nanomaterials in the last couple of decades contributed significantly to the development of the biosensors in terms of sensitivity, catalytic activity, biocompatibility, and robustness. Additionally, nanomaterials help in miniaturization of the sensing platform and helping in the commercial success of portable biosensor kits. Surface engineering equally contributed to the biosensor development by ensuring a reproducible and stable sensing surface, efficient analyte-biorecognition element interaction, and reduced fouling effect in biological solution. Due to nanomaterial integration and surface engineering, biosensors are now equally sensitive to the lab-based sophisticated instruments to detect a wide range of molecules of clinical significance. In this review, various types of biosensors, their designs, and their working principles have been discussed. A detailed account of various types of nanomaterials, their functionalization and characterization have also been discussed. The analytical performances of biosensors for both clinical validation and analyte detection have been incorporated here. The recent trends in advanced biosensors, such as smartphone interface for biosensing, nanozymes, lab-on-a-chip based detection methods have been discussed.
Described is a practical and universal CH functionalization of readily removable N‐benzyl and N‐allyl carbamates, with a wide range of nucleophiles at ambient temperature promoted by Ph3CClO4. The ...metal‐free reaction has an excellent functional‐group tolerance, and displays a broad scope with respect to both N‐carbamates and nucleophile partners (a variety of organoboranes and CH compounds). The synthetic utility in target‐ as well as diversity‐oriented syntheses is demonstrated.
Strategic play: A direct functionalization of the title carbamates with a wide range of nucleophiles has been developed. The reaction proceeds efficiently at low temperature using Ph3CClO4 as an oxidant. Sensitive functional groups are tolerated, thus allowing applications in natural product synthesis, the construction of chemical libraries, and the discovery of potential anticancer targets.
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•The development of alkynyl ligands for the preparation of coinage metal clusters was reviewed.•A comprehensive survey of synthetic methods of alkynyl-protected coinage metal clusters ...was presented.•The functional alkynyl-protected coinage metal clusters were classified and discussed.•The future development trends of alkynyl-protected coinage metal clusters were prospected.
The selection of surface organic ligands is very important for the preparation of coinage metal clusters with precise structures, which can dictate the related properties of metal clusters. Alkynyl ligands, as a class of protecting ligands in metal cluster systems, have been gaining attentions because of the characteristics of both π and σ coordination modes. Specially, alkynyl-protected coinage metal clusters possess rich properties. However, there is no review to systemically summarize the functional properties and structure-functionality correlations of alkynyl-protected coinage metal clusters. In this review, the development of alkynyl ligands for the preparation of coinage metal clusters was reviewed. Additionally, the synthetic approaches of the alkynyl-protected coinage metal clusters were provided. Then, the functional properties of the alkynyl-protected coinage metal clusters were comprehensively summarized. In the end, the prospects and opportunities for the future development were discussed. We believed that the review will motivate the development of functionality-oriented alkynyl-protected coinage metal clusters.
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