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101.
Iridium(I)‐Catalyzed Regioselective CH Activation and Hydrogen‐Isotope Exchange of Non‐aromatic Unsaturated Functionality 下载免费PDF全文
Prof. Dr. William J. Kerr Richard J. Mudd Dr. Laura C. Paterson Dr. Jack A. Brown 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14604-14607
Isotopic labelling is a key technology of increasing importance for the investigation of new C?H activation and functionalization techniques, as well as in the construction of labelled molecules for use within both organic synthesis and drug discovery. Herein, we report for the first time selective iridium‐catalyzed C?H activation and hydrogen‐isotope exchange at the β‐position of unsaturated organic compounds. The use of our highly active [Ir(cod)(IMes)(PPh3)][PF6] (cod=1,5‐cyclooctadiene) catalyst, under mild reaction conditions, allows the regioselective β‐activation and labelling of a range of α,β‐unsaturated compounds with differing steric and electronic properties. This new process delivers high levels of isotope incorporation over short reaction times by using low levels of catalyst loading. 相似文献
102.
Mark P. Waller Thomas Dresselhaus Jack Yang 《Journal of computational chemistry》2013,34(16):1420-1428
Here, we present just a collection of beans (JACOB): an integrated batch‐based framework designed for the rapid development of computational chemistry applications. The framework expedites developer productivity by handling the generic infrastructure tier, and can be easily extended by user‐specific scientific code. Paradigms from enterprise software engineering were rigorously applied to create a scalable, testable, secure, and robust framework. A centralized web application is used to configure and control the operation of the framework. The application‐programming interface provides a set of generic tools for processing large‐scale noninteractive jobs (e.g., systematic studies), or for coordinating systems integration (e.g., complex workflows). The code for the JACOB framework is open sourced and is available at: www.wallerlab.org/jacob . © 2013 Wiley Periodicals, Inc. 相似文献
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Abstract It is shown that the McMillan parameter M = T SAN/T N1 (where T SAN and T NI are respectively the temperatures of the smectic A to nematic (SAN) and the nematic to isotropic (NI) phase transitions) is useful in analysing the crossover between second and first order behaviour of the SNN transition in the nO.m homologous liquid crystal series (the 4-n-alkoxybenzylidene-4′-n-alkylanilines). Using a phase diagram of orientational ordering versus M for this series, as obtained in this work (from E.S.R. and D.S.C), a symmetric tricritical point with mean field exponent β2 = 1 is demonstrated. In a preliminary study of E.S.R. linewidth parameters B and C of nitroxide spin probes dissolved in members of the nO.m series exhibiting a first order SAN transition, critical-type divergences are observed near this transition. In the case where M is closer to 0.959 (the value at the tricritical point), these divergences appear similar to those previously observed in related nO.m members with a second order SAN transition; however, they are considerably enhanced for an M value closer to unity (i.e. more removed from the tricritical point). This indicates the importance of coupling between orientational and positional order parameters in the observed critical-type divergences. 相似文献
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Charles E. Carraher Jr. Van R. Foster H. Michael Molloy Michael L. Taylor Thomas O. Tiernan Jack A. Schroeder 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(1):231-241
The synthesis of polymers derived from the condensation of dipyridine manganese II dichloride with 1,3-di-4-piperidylpro-pane is described. Structural analysis of the polyamines is detailed utilizing results based on infrared, thermal, elemental and solution analyses. 相似文献
106.
Xi Yao Stuart S. Dunn Philseok Kim Meredith Duffy Jack Alvarenga Joanna Aizenberg 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(17):4507-4511
Omniphobic fluorogel elastomers were prepared by photocuring perfluorinated acrylates and a perfluoropolyether crosslinker. By tuning either the chemical composition or the temperature that control the crystallinity of the resulting polymer chains, a broad range of optical and mechanical properties of the fluorogel can be achieved. After infusing with fluorinated lubricants, the fluorogels showed excellent resistance to wetting by various liquids and anti‐biofouling behavior, while maintaining cytocompatiblity. 相似文献
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A convenient and efficient method for the preparation of unsymmetrical and symmetrical diacetylenic ketones bearing a carboxylate group. 相似文献
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