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N-heterocyclic carbenes (NHCs) are well-known as ligands and organocatalysts, but there is no recognition for their catalytic role as a stabilizer through electrostatic interaction rather than electron donation. By utilizing the electrostatic interaction, we herein describe the success of a visible-light-triggered radical-radical cross-coupling of N-alkenoxypyridinium salts and NaI, giving a variety of α-iodo ketones. Computational studies characterize the stabilization role of NHCs.An ideal DNA carrier is one that is capable of effectively condensing DNA into complexes of optimum size and shape, preventing premature decomplexation in the bloodstream and efficiently releasing the DNA into affected cells. In this context, we have developed a novel β-cyclodextrin (β-CD)-based four-arm star-shaped polymer inclusion complex (IC) with arms made of a poly(l-histidine)-based cationic polymer. The polymer was well characterized by gel permeation chromatography, NMR, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. We have also investigated its DNA complexation and release properties. Bisadamantane containing a disulfide bond was synthesized that linked two such poly(l-histidine)-containing β-CD units via guest-host interactions to prepare the presented IC. Besides using the conventional steady-state fluorescence spectroscopy, the ability of this IC to condense DNA to form polyplexes and their release behavior have been established by using the time-resolved fluorpolycation and DNA using TO as a DNA-intercalating dye.Ionic liquids composed of a thiocyanate complex of Ce(III) exhibit bright cyan photoluminescence with a quantum yield close to 40% in addition to paramagnetism. The morphology of a droplet of ionic liquid changes in response to solvent vapor as a stimulus. The emission lifetime and thermal property are characterized. The Weiss temperature is evaluated from the magnetic property measurements, which indicates that antiferromagnetic exchange interaction exists between Ce(III) ions. Insight into the characteristics of the electronic transitions in the Ce(III) complex is obtained using quantum chemical calculations. Thiocyanate complexes of Ce(III) are demonstrated as promising building blocks to produce solvent-free luminescent functional materials.The discovery of carbon fullerene cages and their solids opened a new avenue to build materials from stable cage clusters as "artificial atoms" or "superatoms" instead of atoms. However, cage clusters of other elements are generally not stable. In 2001, ab initio calculations showed that endohedral doping of Zr and Ti atoms leads to highly stable Zr@Si16 fullerene and Ti@Si16 Frank-Kasper polyhedral clusters with large HOMO-LUMO gaps. In 2002, Zr@Ge16 was shown to form a Frank-Kasper polyhedron, suggesting the possibility of designing novel clusters by tuning endohedral and cage atoms. These results were subsequently confirmed from experiments. In the past nearly two decades, many experimental and theoretical studies have been carried out on different clusters, and many very stable cage clusters with possibly high abundance have been found by endohedral doping. Indeed in 2017, Ta@Si16 and Ti@Si16 cage clusters have been synthesized in bulk quantity of about 100 mg using a dry-chemistry method, giving rise to present updated results of the most stable atomic structures and fundamental electronic properties of the endohedrally doped cage clusters. We discuss electronic, magnetic, optical, and catalytic properties in order to shed light on their potential applications. The stability of the doped cage clusters has been correlated to the concept of filling the electronic shells for superatoms such as within a spherical potential model and also using various electron counting rules including Wade-Mingos rules, systems with 18 and 32 electrons, and the spherical aromaticity rule. We also discuss cluster-cluster interaction in cluster dimers and assemblies of some of the promising doped cage clusters in different dimensions. G Protein inhibitor Finally, we give a perspective of this field with a bright future.Over the past several years, hyphenation of native (nondenaturing) liquid chromatography (nLC) methods, such as size exclusion chromatography (SEC), ion exchange chromatography (IEX), and hydrophobic interaction chromatography (HIC) with mass spectrometry (MS) have become increasingly popular to study the size, charge, and structural heterogeneity of protein drug products. Despite the availability of a wide variety of nLC-MS methods, an integrated platform that can accommodate different applications is still lacking. In this study, we described the development of a versatile, sensitive, and robust nLC-MS platform that can support various nLC-MS applications. In particular, the developed platform can tolerate a wide range of LC flow rates and high salt concentrations, which are critical for accommodating different nLC methods. In addition, a dopant-modified desolvation gas can be readily applied on this platform to achieve online charge-reduction native MS, which improves the characterization of both heterogeneous and labile biomolecules. Finally, we demonstrated that this nLC-MS platform is highly sensitive and robust and can be routinely applied in protein drug characterization.The mechanism of the organocatalytic Cope rearrangement is elucidated through a combined computational and experimental approach. As reported previously, hydrazides catalyze the Cope rearrangement of 1,5-hexadiene-2-carboxaldehydes via iminium ion formation, and seven- and eight-membered ring catalysts are more active than smaller ring sizes. In the present work, quantum mechanical computations and kinetic isotope effect experiments demonstrate that the Cope rearrangement step, rather than iminium formation, is rate-limiting. The computations further explain how the hydrazide catalyst lowers the free-energy barrier of the Cope rearrangement via an associative transition state that is stabilized by enehydrazine character. The computations also explain the catalyst ring size effect, as larger hydrazide rings are able to accommodate optimal transition-state geometries that minimize the unfavorable lone-pair repulsion between neighboring nitrogen atoms and maximize the favorable hyperconjugative donation from each nitrogen atom into neighboring electron-poor sigma bonds, with the seven-membered catalyst achieving a nearly ideal transition-state geometry that is comparable to that of an unconstrained acyclic catalyst.