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891.
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Dr. Maxime Horeau Dr. Guillaume Lautrette Dr. Barbara Wicher Dr. Virginie Blot Prof. Jacques Lebreton Dr. Muriel Pipelier Prof. Didier Dubreuil Dr. Yann Ferrand Dr. Ivan Huc 《Angewandte Chemie (International ed. in English)》2017,56(24):6823-6827
The development of foldamer-based receptors is driven by the design of monomers with specific properties. Herein, we introduce a pyridazine-pyridine-pyridazine diacid monomer and its incorporation into helical aromatic oligoamide foldamer containers. This monomer codes for a wide helix diameter and can sequester metal ions on the inner wall of the helix cavity. Crystallographic studies and NMR titrations show that part of the metal coordination sphere remains available and may then promote the binding of a guest within the cavity. In addition to metal coordination, binding of the guest is assisted by cooperative interactions with the helix host, thereby resulting in significant enhancements depending on the foldamer sequence, and in slow guest capture and release on the NMR time scale. In the absence of metal ions, the pyridazine-pyridine-pyridazine monomer promotes an extended conformation of the foldamer that results in aggregation, including the formation of an intertwined duplex. 相似文献
893.
Nonlinear Dynamics - Started in Wuhan, China, the COVID-19 has been spreading all over the world. We calibrate the logistic growth model, the generalized logistic growth model, the generalized... 相似文献
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895.
Elucidation of a side reaction occurring during nitroxide‐mediated polymerization of cyclic ketene acetals by tandem mass spectrometric end‐group analysis of aliphatic polyesters
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897.
898.
Iodonium‐polyoxometalate and thianthrenium‐polyoxometalate as new one‐component UV photoinitiators for radical and cationic polymerization
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Haifaa Mokbel Pu Xiao Corine Simonnet‐Jégat Frederic Dumur Didier Gigmes Joumana Toufaily Tayssir Hamieh Jean Pierre Fouassier Jacques Lalevée 《Journal of polymer science. Part A, Polymer chemistry》2015,53(8):981-989
Four novel onium salts (onium‐polyoxometalate) have been synthesized and characterized. They contain a diphenyliodonium or a thianthrenium (TH) moiety and a polyoxomolybdate or a polyoxotungstate as new counter anions. Outstandingly, these counter anions are photochemically active and can sensitize the decomposition of the iodonium or TH moiety through an intramolecular electron transfer. The phenyl radicals generated upon UV light irradiation (Xe–Hg lamp) are very efficient to initiate the radical polymerization of acrylates. Cations are also generated for the cationic polymerization of epoxides. Remarkably, these novel iodonium and TH salts are characterized by a higher reactivity compared with that of the diphenyliodonium hexafluorophosphate and the commercial TH salt, respectively. Interpenetrating polymer networks can also be obtained under air through a concomitant cationic/radical photopolymerization of an epoxy/acrylate blend (monomer conversions > 65%). The photochemical mechanisms are studied by steady‐state photolysis, cyclic voltammetry, and electron spin resonance techniques. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 981–989 相似文献
899.
Feriel Rekhroukh Rmy Brousses Abderrahmane Amgoune Didier Bourissou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(4):1282-1285
Migratory insertion of alkenes into gold–carbon bonds, a fundamental yet unprecedented organometallic transformation, has been investigated from a discrete (P,C) cyclometalated gold(III) dimethyl complex. Methide abstraction by B(C6F5)3 is shown to generate a highly reactive cationic AuIII complex that evolves spontaneously by C6F5 transfer from boron. In the presence of norbornene, migratory insertion into the Au C bond proceeds readily. The resulting norbornyl complex is efficiently trapped with pyridines or chloride to give stable four‐coordinate adducts. 相似文献
900.
A four steps partial synthesis of (-)-polygodial (1) has been achieved, using (-)-drimenol (2) as starting material. 相似文献