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951.
Stefan Werner Dr. Helgard Ebert Bob‐Dan Lechner Frank Lange Anja Achilles Ruth Bärenwald Silvio Poppe Prof. Dr. Alfred Blume Prof. Dr. Kay Saalwächter Prof. Dr. Carsten Tschierske Prof. Dr. Kirsten Bacia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(24):8840-8850
A novel class of bolapolyphile (BP) molecules are shown to integrate into phospholipid bilayers and self‐assemble into unique sixfold symmetric domains of snowflake‐like dendritic shapes. The BPs comprise three philicities: a lipophilic, rigid, π–π stacking core; two flexible lipophilic side chains; and two hydrophilic, hydrogen‐bonding head groups. Confocal microscopy, differential scanning calorimetry, XRD, and solid‐state NMR spectroscopy confirm BP‐rich domains with transmembrane‐oriented BPs and three to four lipid molecules per BP. Both species remain well organized even above the main 1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphocholine transition. The BP molecules only dissolve in the fluid membrane above 70 °C. Structural variations of the BP demonstrate that head‐group hydrogen bonding is a prerequisite for domain formation. Independent of the head group, the BPs reduce membrane corrugation. In conclusion, the BPs form nanofilaments by π stacking of aromatic cores, which reduce membrane corrugation and possibly fuse into a hexagonal network in the dendritic domains. 相似文献
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Florian G. Perrin Dr. Gregor Kiefer Loïc Jeanbourquin Sophie Racine Daniele Perrotta Prof. Jérôme Waser Dr. Rosario Scopelliti Prof. Kay Severin 《Angewandte Chemie (International ed. in English)》2015,54(45):13393-13396
The chemical reactivity of 1‐alkynyltriazenes has been investigated and is found to parallel the reactivity of ynamides. The similarity in reactivity of these two classes of compounds is demonstrated by addition reactions with acids, by cycloaddition reactions with ketenes, tetracyanoethene, and cyclopropanes, as well as by intramolecular cyclization reactions. The presence of reactive triazene groups in the products enables subsequent transformations. Overall, our results suggest that 1‐alkynyltriazenes should become valuable reagents in synthetic organic chemistry. 相似文献
954.
Hung Kay Lee Yu Peng Steven C. F. Kui Ze-Ying Zhang Zhong-Yuan Zhou Thomas C. W. Mak 《欧洲无机化学杂志》2000,2000(10):2159-2162
The thermally stable nickel(II) diamides [NiL2] [L = −N(SiMe3)(8-C9H6N) ( 1 ), −N(SitBuMe2)(8-C9H6N) ( 2 )] have been synthesized from the reaction of NiCl2 with the appropriate lithium amide. X-ray crystallography revealed that the amido ligands bind in a chelating manner, forming a distorted tetrahedral environment around the nickel center. Complexes 1 and 2 have magnetic moments of 3.05 and 2.74 μB, respectively, which indicate a d8 electronic configuration with two unpaired electrons. 相似文献
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We report on variable-angle deuterium NMR measurements of nematic liquid-crystalline side-chain polymers, where we have found proof of the existence of a biaxial nematic phase in a system with a side-on attachment of the mesogenic group to the polymer backbone. This provides efficient coupling to the polymer backbone and thus stabilizes the as yet elusive biaxial phase. The experimental approach is validated on a uniaxial end-on nematic polymer, and the reliability of the results is investigated in detail using two-dimensional correlation spectra, providing information on director distribution effects. 相似文献