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Bert C. Lynn Jesus V. Mallén Servando Muñoz Minsook Kim George W. Gokel 《Supramolecular chemistry》2013,25(3-4):195-197
Abstract Bola-amphiphiles having two aza-18-crown-6 ether rings attached by a covalent spacer (O—O) and an analogous tris (macrocycle) (O—O—O) have been prepared and their cation complexation behavior has been assessed by fast atom bombardment and collisionally activated dissociation tandem mass spectrometry; the key finding is that two cations may simultaneously be complexed by a two- or three-crown system and that this complexation may also involve an anion. 相似文献
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A One‐Pot Synthesis of N‐Aryl‐2‐Oxazolidinones and Cyclic Urethanes by the Lewis Base Catalyzed Fixation of Carbon Dioxide into Anilines and Bromoalkanes
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Teemu Niemi Dr. Jesus E. Perea‐Buceta Dr. Israel Fernández Otto‐Matti Hiltunen Vili Salo Sari Rautiainen Dr. Minna T. Räisänen Prof. Timo Repo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10355-10359
The multicomponent assembly of pharmaceutically relevant N‐aryl‐oxazolidinones through the direct insertion of carbon dioxide into readily available anilines and dibromoalkanes is described. The addition of catalytic amounts of an organosuperbase such as Barton's base enables this transformation to proceed with high yields and exquisite substrate functional‐group tolerance under ambient CO2 pressure and mild temperature. This report also provides the first proof‐of‐principle for the single‐operation synthesis of elusive seven‐membered ring cyclic urethanes. 相似文献
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Jörgen Metsik Kristjan Saal Uno Mäeorg Rünno Lõhmus Silver Leinberg Hugo Mändar Margus Kodu Martin Timusk 《Journal of Polymer Science.Polymer Physics》2014,52(8):561-571
Transparent [90% transmittance at 550 nm at a sheet resistance (Rs) of 279 Ω sq?1] poly(3,4‐ethylenedioxythiophene) (PEDOT) films with electrical conductivities up to 1354 S cm?1 are prepared using base‐inhibited vapor phase polymerization at atmospheric pressure. The influence of reaction conditions, such as temperature and growth time, on the film formation is investigated. A simple and convenient two‐electrode method is used for the in situ measurement of resistance, enabling to investigate the growth mechanism of polymer films and the influence of different parameters (relative humidity and the amount of oxidant) on the film growth. Low humidity exerts a detrimental effect on film growth and conductivity. In situ Rs measurements suggest that a large structural change occurs upon washing the PEDOT‐oxidant film. © 2014 Wiley Periodicals, Inc. J Polym Sci Part B: Polym. Phys. 2014 , 52, 561–571 相似文献
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Genildo de Jesus Nery 《代数通讯》2020,48(4):1567-1576
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Alexander Tuan-Huy Duong Bryan J. Simmons Mohammad Parvez Alam Jesus Campagna Neil K. Garg Varghese John 《Tetrahedron letters》2019,60(3):322-326
This study describes our development of a microfluidic reaction scheme for the synthesis of fused indoline ring systems found in several bioactive compounds. We have utilized a continuous-flow microfluidic reactor for the reaction of hydrazines with latent aldehydes through the interrupted Fischer indolization reaction to form fused indoline and azaindoline products. We have identified optimal conditions and evaluated the scope of this microfluidic reaction using various hydrazine and latent aldehyde surrogates. This green chemistry approach can be of general utility to rapidly produce indoline scaffolds and intermediates in a continuous manner. 相似文献
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Gatto Claudia C. Chagas Marcio A. S. Lima Iariane J. Mello Andrade Francyelli Silva Hugo D. Abrantes Gabrielly R. Lacerda Elisângela P. S. 《Transition Metal Chemistry》2019,44(4):329-340
Transition Metal Chemistry - The present study reports the synthesis and crystal structures of Cu(II) complexes with pyridoxal S-allyldithiocarbazate (H2L1) and pyridoxal thiosemicarbazones... 相似文献