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751.
752.
Sascha Reith Serhiy Demeshko Beatrice Battistella Alexander Reckziegel Christian Schneider Andreas Stoy Crispin Lichtenberg Franc Meyer Dominik Munz C. Gunnar Werncke 《Chemical science》2022,13(26):7907
Imidyl and nitrene metal species play an important role in the N-functionalisation of unreactive C–H bonds as well as the aziridination of olefines. We report on the synthesis of the trigonal imido iron complexes [Fe(NMes)L2]0,− (L = –N{Dipp}SiMe3); Dipp = 2,6-diisopropyl-phenyl; Mes = (2,4,6-trimethylphenyl) via reaction of mesityl azide (MesN3) with the linear iron precursors [FeL2]0,−. UV-vis-, EPR-, 57Fe Mössbauer spectroscopy, magnetometry, and computational methods suggest for the reduced form an electronic structure as a ferromagnetically coupled iron(ii) imidyl radical, whereas oxidation leads to mixed iron(iii) imidyl and electrophilic iron(ii) nitrene character. Reactivity studies show that both complexes are capable of H atom abstraction from C–H bonds. Further, the reduced form [Fe(NMes)L2]− reacts nucleophilically with CS2 by inserting into the imido iron bond, as well as electrophilically with CO under nitrene transfer. The neutral [Fe(NMes)L2] complex shows enhanced electrophilic behavior as evidenced by nitrene transfer to a phosphine, yet in combination with an overall reduced reactivity.A pair of trigonal imido iron complexes ([Fe(NMes)L2]0,−) in two oxidation states is reported. The anionic complex K{crypt.222}[Fe(NMes)L2] is best described as an iron(ii) imide. 相似文献
753.
Ronja Rabea Paschke Swantje Mohr Dr. Sascha Lange Prof. Dr. Adam Lange Dr. Jacek Kozuch 《Angewandte Chemie (International ed. in English)》2023,62(47):e202309069
Viroporins are small ion channels in membranes of enveloped viruses that play key roles during viral life cycles. To use viroporins as drug targets against viral infection requires in-depth mechanistic understanding and, with that, methods that enable investigations under in situ conditions. Here, we apply surface-enhanced infrared absorption (SEIRA) spectroscopy to Influenza A M2 reconstituted within a solid-supported membrane, to shed light on the mechanics of its viroporin function. M2 is a paradigm of pH-activated proton channels and controls the proton flux into the viral interior during viral infection. We use SEIRA to track the large-scale reorientation of M2’s transmembrane α-helices in situ during pH-activated channel opening. We quantify this event as a helical tilt from 26° to 40° by correlating the experimental results with solid-state nuclear magnetic resonance-informed computational spectroscopy. This mechanical motion is impeded upon addition of the inhibitor rimantadine, giving a direct spectroscopic marker to test antiviral activity. The presented approach provides a spectroscopic tool to quantify large-scale structural changes and to track the function and inhibition of the growing number of viroporins from pathogenic viruses in future studies. 相似文献
754.
K. Micha Pietrusiewicz Maciej Ku
nikowski Wanda Wieczorek Alberto Brandi 《Heteroatom Chemistry》1992,3(1):37-40
Single-crystal X-ray diffraction experiments have been performed on diphenylvinylphosphine sulfide ( 1 ): C14H13PS, space group P 21/c, a = 10.186(1) Ǎ, b = 11.918(1) Å, c = 11.426 Å, β = 112.22(2)°, V = 1284.1(2) Å3, Z = 4, and diphenylvinylphosphine selenide ( 2 ): C14H13PSe, space group Pbca, a = 9.141 (3) Å, b = 16.458 (1) Å, c = 17.451 (1) Å, V = 2625.4 (9) Å3, Z = 8. The structures were solved by direct methods and were refined by full matrix least-squares calculations to R = 0.046 and Rw = 0.058 using 2554 unique reflections with I > 3σ(I) in the case of 1 , and to R = 0.052 and Rw = 0.065 using 1953 unique reflections with I > 3σ(I) in the case of 2 . In close analogy to the previously studied vinyl phosphine oxides both 1 and 2 were found to exist in the s-cis conformation with the pertinent CC PX dihedral angles equal to 12.5° and 2.9° for 1 and 2 , respectively. 相似文献
755.
Wanja Gschwind Dr. Brian D. McCarthy Nina F. Suremann Prof. Dr. Sascha Ott 《欧洲无机化学杂志》2023,26(27):e202300216
Water is known to play an important role for the crystallization and stability of Zr-based metal-organic frameworks (MOFs). This work investigates its effect on the vapor-assisted conversion (VAC) synthesis of UiO-67 MOF thin films on Au-coated Si substrates. We demonstrate the equilibration processes taking place during the VAC procedure, confirming the gradual equilibration of all solutions upon heating. The presence of water affects the vapor phase composition but does not significantly impact the acetic acid equilibration rate. However, the preparation of UiO-67 thin films by VAC is highly sensitive to the water content in the reaction. Some water is required for the formation of the zirconium clusters, but excessive water in the reaction vial yields poorly crystalline materials. Atmospheric water that is taken up by the vapor source can be sufficient to reduce crystallinity dramatically. This complication can be partially overcome by increasing the amount of acetic acid in the vapor source. 相似文献
756.
Felix Geist Dr. Sebastián Martínez Dr. Jacqueline Ramler Dr. Kai Oberdorf Lisa Brändler Sascha Reith Prof. Dr. Crispin Lichtenberg 《欧洲无机化学杂志》2023,26(32):e202300546
Bis[dibenzobismepine], a dibismuthane composed of two bismepine units (R2Bi−BiR2), was synthesized and fully characterized (R2=(C6H4CH)2). Reactions of this dibismuthane with diphenyl dichalcogenides, dibenzoylperoxide, and elemental chalcogens have been investigated. All products of these reactions have been isolated and fully characterized, including a series of compounds R2Bi−E−BiR2 (E=O−Te). These species contain two olefin units of the bismepine moieties and a chalcogen atom as potential coordination sites. The potential of these species to act as hybrid tridentate chalcogen/olefin ligands with bismuth atoms as structure-determining elements in the backbone has been investigated by theoretical approaches, aiming at the complexation of CoI, RhI, IrI and Ni0, Pd0, Pt0. The analytical techniques applied in this work include heteronuclear and 2D NMR spectroscopy, elemental analysis, single-crystal X-ray diffraction analysis, and DFT calculations. 相似文献
757.
Dr. Irene Regeni Rituparno Chowdhury Kai Terlinden Dr. Shinnosuke Horiuchi Dr. Julian J. Holstein Dr. Sascha Feldmann Prof. Dr. Guido H. Clever 《Angewandte Chemie (International ed. in English)》2023,62(40):e202308288
A strategy to engineer the stacking of diketopyrrolopyrrole (DPP) dyes based on non-statistical metallosupramolecular self-assembly is introduced. For this, the DPP backbone is equipped with nitrogen-based donors that allow for different discrete assemblies to be formed upon the addition of Pd(II), distinguished by the number of π-stacked chromophores. A Pd3L6 three-ring, a heteroleptic Pd2L2L′2 ravel composed of two crossing DPPs (flanked by two carbazoles), and two unprecedented self-penetrated motifs (a Pd2L3 triple and a Pd2L4 quadruple stack), were obtained and systematically investigated. With increasing counts of stacked chromophores, UV/Vis absorptions red-shift and emission intensities decrease, except for compound Pd2L2L′2, which stands out with an exceptional photoluminescence quantum yield of 51 %. This is extraordinary for open-shell metal containing assemblies and explainable by an intra-assembly FRET process. The modular design and synthesis of soluble multi-chromophore building blocks offers the potential for the preparation of nanodevices and materials with applications in sensing, photo-redox catalysis and optics. 相似文献
758.
The structural investigation of two enantiomers of the phosphoroorganic selenium-containing compound [(+)C10H16NO2PSe ( 1 ) and (−)C10H16NO2PSe ( 1 ′)] was carried out. The absolute configuration at the P and C3 atoms was found to be R for compound 1 and, respectively, S for compound 1 ′. 相似文献