Omarewing1555

The development of efficient approaches to access sulfonyl fluorides is of great significance because of the widespread applications of these structural motifs in many areas, among which the emerging sulfur(vi) fluoride exchange (SuFEx) click chemistry is the most prominent. Here, we report the first three-component aminofluorosulfonylation of unactivated olefins by merging photoredox-catalyzed proton-coupled electron transfer (PCET) activation with radical relay processes. Various aliphatic sulfonyl fluorides featuring a privileged 5-membered heterocyclic core have been efficiently afforded under mild conditions with good functional group tolerance. The synthetic potential of the sulfonyl fluoride products has been examined by diverse transformations including SuFEx reactions and transition metal-catalyzed cross-coupling reactions. Mechanistic studies demonstrate that amidyl radicals, alkyl radicals and sulfonyl radicals are involved in this difunctionalization transformation.Molecular spoked wheels with D 3h and C s symmetry are synthesized by Vollhardt trimerization of C 2v-symmetric dumbbell structures with central acetylene units and subsequent intramolecular ring closure. Scanning tunneling microscopy of the D 3h-symmetric species at the solid/liquid interface on graphite reveals triporous chiral honeycomb nanopatterns in which the alkoxy side chains dominate the packing over the carboxylic acid groups, which remain unpaired. In contrast, C s-symmetric isomers partially allow for pairing of the carboxylic acids, which therefore act as a probe for the reduced alkoxy chain nanopattern stabilization. This observation also reflects the adsorbate substrate symmetry mismatch, which leads to an increase of nanopattern complexity and unexpected templating of alkoxy side chains along the graphite armchair directions. State-of-the-art GFN-FF calculations confirm the overall structure of this packing and attribute the unusual side-chain orientation to a steric constraint in a confined environment. These calculations go far beyond conventional simple space-filling models and are therefore particularly suitable for this special case of molecular packing.A palladium-catalyzed C-O bond formation reaction between phenols and allenylic carbonates to give 2,3-allenic aromatic ethers with decent to excellent yields under mild reaction conditions has been described. A variety of synthetically useful functional groups are tolerated and the synthetic utility of this method has been demonstrated through a series of transformations of the allene moiety. By applying this reaction as the key step, the total syntheses of naturally occurring allenic aromatic ethers, eucalyptene and terricollene A (first synthesis; 4.5 g gram scale), have been accomplished.Acknowledging its unique conical lumen structure, Mycobacterium smegmatis porin A (MspA) was the first type of nanopore that has successfully sequenced DNA. Recent developments of nanopore single molecule chemistry have also suggested MspA to be an optimum single molecule reactor. However, further investigations with this approach require heavy mutagenesis which is labor intensive and requires high end instruments for purifications. We here demonstrate an efficient and economic protocol which performs rapid and multiplex preparation of a variety of MspA mutants. The prepared MspA mutants were demonstrated in operations such as nanopore insertion, sequencing, optical single channel recording (oSCR), nanopore single molecule chemistry and nanopore rectification. The performance is no different from that of pores however prepared by other means. The time of all human operations and the cost for a single batch of preparation have been minimized to 40 min and 0.4$, respectively. This method is extremely useful in the screening of new MspA mutants, which has an urgent requirement in further investigations of new MspA nanoreactors. Its low cost and simplicity also enable efficient preparations of MspA nanopores for both industrial manufacturing and academic research.A novel salt-inclusion fluoroiodate [GaF(H2O)][IO3F] derived from CsIO2F2 was ingeniously obtained through anisotropic polycation substitution. Because the catenulate [GaF(H2O)]2+ framework serves as a template for the favorable assembly of the polar [IO3F]2- groups and contributes to the nonlinear coefficient, [GaF(H2O)][IO3F] exhibits a greatly improved second-harmonic generation (SHG) effect of 10 times that of KH2PO4 (KDP) and a considerable band gap of 4.34 eV compared to the parent compound CsIO2F2 (3 × KDP, 4.5 eV). Particularly, to the best of our knowledge, [GaF(H2O)][IO3F] has the largest laser-induced damage threshold (LDT) of 140 × AgGgS2 of the reported iodates. All these results signify that [GaF(H2O)][IO3F] is a promising nonlinear optical (NLO) crystal. This work also proposes that anisotropic polycation substitution is an effective approach to optimize the SHG effect and develop excellent NLO materials.The Cope rearrangement of 2,3-divinyloxiranes, a rare example of epoxide C-C bond cleavage, results in 4,5-dihydrooxepines which are amenable to hydrolysis, furnishing 1,6-dicarbonyl compounds containing two contiguous stereocenters at the 3- and 4-positions. We employ an Ir-based alkene isomerization catalyst to form the reactive 2,3-divinyloxirane in situ with complete regio- and stereocontrol, which translates into excellent control over the stereochemistry of the resulting oxepines and ultimately to an attractive strategy towards 1,6-dicarbonyl compounds.Human histone deacetylase 8 (HDAC8) is a key hydrolase in gene regulation and an important drug-target. High-resolution structures of HDAC8 in complex with substrates or inhibitors are available, which have provided insights into the bound state of HDAC8 and its function. Here, using long all-atom unbiased molecular dynamics simulations and Markov state modelling, we show a strong correlation between the conformation of aromatic side chains near the active site and opening and closing of the surrounding functional loops of HDAC8. We also investigated two mutants known to allosterically downregulate the enzymatic activity of HDAC8. Based on experimental data, we hypothesise that I19S-HDAC8 is unable to release the product, whereas both product release and substrate binding are impaired in the S39E-HDAC8 mutant. The presented results deliver detailed insights into the functional dynamics of HDAC8 and provide a mechanism for the substantial downregulation caused by allosteric mutations, including a disease causing one.Natural porous materials such as nanoporous clays are used as green and low-cost adsorbents and catalysts. The key factors determining their performance in these applications are the pore morphology and surface activity, which are typically represented by properties such as specific surface area, pore volume, micropore content and pH. The latter may be modified and tuned to specific applications through material processing and/or chemical treatment. Characterization of the material, raw or processed, is typically performed experimentally, which can become costly especially in the context of tuning of the properties towards specific application requirements and needing numerous experiments. In this work, we present an application of tree-based machine learning methods trained on experimental datasets to accelerate the characterization of natural porous materials. The resulting models allow reliable prediction of the outcomes of experimental characterization of processed materials (R 2 from 0.78 to 0.99) as well as identification of key factors contributing to those properties through feature importance analysis. Furthermore, the high throughput of the models enables exploration of processing parameter-property correlations and multiobjective optimization of prototype materials towards specific applications. We have applied these methodologies to pinpoint and rationalize optimal processing conditions for clays exploitable in acid catalysis. One of such identified materials was synthesized and tested revealing appreciable acid character improvement with respect to the pristine material. Specifically, it achieved 79% removal of chlorophyll-a in acid catalyzed degradation.Pore alignment and linker orientation influence diffusion and guest molecule interactions in metal-organic frameworks (MOFs) and play a pivotal role for successful utilization of MOFs. The crystallographic orientation and the degree of orientation of MOF films are generally determined using X-ray diffraction. However, diffraction methods reach their limit when it comes to very thin films, identification of chemical connectivity or the orientation of organic functional groups in MOFs. Cu-based 2D MOF and 3D MOF films prepared via layer-by-layer method and from aligned Cu(OH)2 substrates were studied with polarization-dependent Fourier-transform infrared (FTIR) spectroscopy in transmission and attenuated total reflection configuration. Thereby, the degrees for in-plane and out-of-plane orientation, the aromatic linker orientation and the initial alignment during layer-by-layer MOF growth, which is impossible to investigate by laboratory XRD equipment, was determined. Experimental IR spectra correlate with theoretical explanations, paving the way to expand the principle of IR crystallography to oriented, organic-inorganic hybrid films beyond MOFs.Aquation is often acknowledged as a necessary step for metallodrug activity inside the cell. Hemilabile ligands can be used for reversible metallodrug activation. We report a new family of osmium(ii) arene complexes of formula [Os(η6-C6H5(CH2)3OH)(XY)Cl]+/0 (1-13) bearing the hemilabile η6-bound arene 3-phenylpropanol, where XY is a neutral N,N or an anionic N,O- bidentate chelating ligand. Os-Cl bond cleavage in water leads to the formation of the hydroxido/aqua adduct, Os-OH(H). In spite of being considered inert, the hydroxido adduct unexpectedly triggers rapid tether ring formation by attachment of the pendant alcohol-oxygen to the osmium centre, resulting in the alkoxy tethered complex [Os(η6-arene-O-κ1)(XY)] n+. Complexes 1C-13C of formula [Os(η6κ1-C6H5(CH2)3OH/O)(XY)]+ are fully characterised, including the X-ray structure of cation 3C. Tether-ring formation is reversible and pH dependent. Osmium complexes bearing picolinate N,O-chelates (9-12) catalyse the hydrogenation of pyruvate to lactate. Intracellular lactate production upon co-incubation of complex 11 (XY = 4-Me-picolinate) with formate has been quantified inside MDA-MB-231 and MCF7 breast cancer cells. The tether Os-arene complexes presented here can be exploited for the intracellular conversion of metabolites that are essential in the intricate metabolism of the cancer cell.The halogen bond is a special non-covalent interaction, which can represent a powerful tool in supramolecular chemistry. Although the halogen bond offers several advantages compared to the related hydrogen bond, it is currently still underrepresented in polymer science. The structural related hydrogen bonding assumes a leading position in polymer materials containing supramolecular interactions, clearly indicating the high potential of using halogen bonding for the design of polymeric materials. The current developments regarding halogen bonding containing polymers include self-assembly, photo-responsive materials, self-healing materials and others. These aspects are highlighted in the present perspective. Noradrenaline bitartrate monohydrate Furthermore, a perspective on the future of this rising young research field is provided.