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《Mendeleev Communications》2022,32(6):792-794
Alkyl-H-phosphinic acid alkyl esters are synthesized in 65–71% yield via chemoselective reaction of alkyl bromides with available alkyl-H-phosphinic acids (60–65 °C, Et3N). The latter are prepared, in turn, by direct phosphorylation of alkyl bromides with red phosphorus under phase-transfer conditions. 相似文献
75.
Xiaojuan Liu Qingqing Wen Prof. Dr. Li Xiang Dr. Xuebing Leng Prof. Dr. Yaofeng Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(24):5494-5499
The synthesis and catalytic applications of trivalent rare-earth metal alkyl complexes have been well developed, but the chemistry of divalent rare-earth metal alkyl complexes lagged much behind. Herein, we report the synthesis, structure, and catalytic applications of a samarium(II) monoalkyl complex supported by a β-diketiminato-based tetradentate ligand, [LSmCH(SiMe3)2] (L=[MeC(NDipp)CHC(Me)NCH2CH2N(Me)CH2CH2NMe2]−, Dipp=2,6-(iPr)2C6H3). This complex is synthesized by the salt metathesis reaction of samarium iodide [LSm(μ-I)]2 and KCH(SiMe3)2 in 63 % yield. Its structure is characterized by single-crystal X-ray diffraction, showing a distorted square-pyramid coordination geometry. This samarium(II) monoalkyl complex exhibits high catalytic activity in the hydrosilylation of aryl and methyl-substituted unsymmetrical internal alkynes with secondary hydrosilanes, selectively providing the α-(E) products in high yields. 相似文献
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Dr. Luis M. Mori‐Quiroz Kirk W. Shimkin Dr. Sina Rezazadeh Ryan A. Kozlowski Prof. Dr. Donald A. Watson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15654-15658
The oxidative copper‐catalyzed cross‐coupling of functionalized alkyl boronic esters with primary amides is reported. Through the identification of appropriate diketimine ligands, conditions for efficient coupling of both primary and secondary alkyl boronic esters with diverse primary amides, including acetamide, have been developed. 相似文献
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Inside Cover: Naphthalene‐Functionalized,Photoluminescent Room Temperature Ionic Liquids Bearing Small Counterions (Chem. Eur. J. 18/2016) 下载免费PDF全文
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Chitoshi Kitamura 《Chemical record (New York, N.Y.)》2012,12(5):506-514
In the solution state, there were no notable differences between the optical properties of a range of alkyl‐substituted tetracenes. However, in the solid state, their photophysical properties changed with respect to the length, shape, number, and substitution pattern of the alkyl side chains, as well as the distribution of two regioisomers. Remarkably, in the solid state, 1,4,7,10‐tetraisopropyltetracene exhibited the highest reported fluorescence quantum yield of any tetracene derivative (0.90). The changes in the optical characteristics of these tetracenes according to the arrangement of the tetracene rings and the color‐change mechanism in the solid state are discussed. Moreover, the world record in solid‐state fluorescence efficiency in acenes larger than anthracene is described. DOI 10.1002/tcr.201200003 相似文献
80.
《Macromolecular bioscience》2017,17(11)
An increased sustainabile awarness has inspired the development of new polymeric networks in a remarkable way and this strive should be combined with environmentally concerned end‐uses. Therefore, a UV‐crosslinked polyhydroxyurethane film with antibacterial properties is developed. First, a hydroxyurethane precursor is synthesized using aminolysis condensation, circumventing the use of isocyanates. The films are subsequently crosslinked under solvent‐free conditions through a UV‐triggered thiol‐ene mechanism. The reactions are monitored by 1H nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy, and the networks have gel contents above 90%, and are transparent, hydrophilic, and highly flexible. Antibacterial properties are achieved by a controlled quaternization of the network's tertiary‐amine and methylation of thiol‐ether functionality, resulting in quaternary ammonium compounds (QACs) and sulfonium compounds. The antibacterial properties are evaluated against both Escherichia coli and Staphylococcus aureus using the agar plate diffusion and tube shaking methods. The QAC‐loaded films exhibit outstanding bactericide properties (>99.9%) and the antibacterial mechanism is demonstrated to be a dual killing mechanism, i.e., diffusion killing and contact active killing. 相似文献