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Patrick W. Antoni Alexandra V. Mackenroth Dr. Florian F. Mulks Dr. Matthias Rudolph Prof. Dr. Günter Helmchen Prof. Dr. A. Stephen K. Hashmi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(37):8235-8238
A sulfilimine-based Group 9 transition-metal-catalysed C−H amidation procedure is reported. Dibenzothiophene-based sulfilimines were shown to constitute a class of novel amidation reagents which enable the transfer of a wide range of N-sulfonyl and N-acyl moieties. It was demonstrated that sulfilimines, which are easily accessible from cheap reagents, are safe-to-handle and represent broadly applicable amidation reagents. The dibenzothiophene can be recycled after use. The C−H amidation was shown to proceed with high selectivity and gave the mono-amidated products, mostly in good to excellent yields. 相似文献
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Christine Weber Sarah Rogers Antje Vollrath Stephanie Hoeppener Tobias Rudolph Nicole Fritz Richard Hoogenboom Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2013,51(1):139-148
A series of comb polymers consisting of a methacrylate backbone and poly(2‐ethyl‐2‐oxazoline) (PEtOx) side chains was synthesized by a combination of cationic ring‐opening polymerization and reversible addition–fragmentation chain transfer polymerization. Small‐angle neutron scattering (SANS) studies revealed a transition from an ellipsoidal to a cylindrical conformation in D2O around a backbone degree of polymerization of 30. Comb‐shaped PEtOx has lowered Tg values but a similar elution behavior in liquid chromatography under critical conditions in comparison to its linear analog was observed. The lower critical solution temperature behavior of the polymers was investigated by turbidimetry, dynamic light scattering, transmission electron microscopy, and SANS revealing decreasing Tcp in aqueous solution with increasing molar mass, the presence of very few aggregated structures below Tcp, a contraction of the macromolecules at temperatures 5 °C above Tcp but no severe conformational change of the cylindrical structure. In addition, the phase diagram including cloud point and coexistence curve was developed showing an LCST of 75 °C of the binary mixture poly[oligo(2‐ethyl‐2‐oxazoline)methacrylate]/water. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
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Long-range acoustic transport of excitons in GaAs quantum wells (QWs) is demonstrated. The mobile strain field of a surface acoustic wave creates a dynamic lateral type I modulation of the conduction and valence bands in a double-quantum-well (DQW) structure. This mobile potential modulation transports long-living indirect excitons in the DQW over several hundreds of μm. 相似文献
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