58 research outputs found
New approaches to aromatic substitution reactions with carbon electrophiles
The thesis gives an account of work directed towards developing new reagent systems and methodology, with particular reference to the Friedel–Crafts and Vilsmeier–Haack reactions of aromatic and heteroaromatlc compounds. Ways of improving regioselectivity and developing a stereoselective Friedel–Crafts reaction have been investigated for a range of hetero-atom stabilised carbocations. This work is divided into two main areas: (1) the synthesis and use of pyrophosphoryl chloride in the Vilsmeier–Haack reaction, the results of this has shed new light on the mechanism of this classical reaction; (2) the control of the Friedel–Crafts reactions of bi-functional derivatives of glyoxylic acid and the use of chiral relays to induce diastereoselectivity. [Continues.
Interaction Mechanism Insights on the Solvation of Fullerene B(80)with Choline-based Ionic Liquids
Beyond carbon allotropes, other nanostructures such as fullerene B80 are attracting a growing interest due to their potential applications. The use of new materials based on fullerene B80 is still in a premature stage; however many of these applications would require the use of B80 in solution. This paper reports an unprecedented density functional theory (DFT) analysis on the interaction mechanism between B80 and two choline-based ionic liquids as a first insight for the fullerene B80 solvation by ionic liquids. The analysis of properties such as binding energies, charge distributions or intermolecular interactions shed light on the main features, which should govern interaction between ionic liquids and fullerene B80. In addition, the optimization of systems composed by six ionic pairs around a fullerene B80 has supplied some information about the first solvation shell at the molecular level. As a summary, this paper provides the first insights in the rational design of ionic liquids with suitable properties for the solvation of B80.Gregorio García acknowledges the funding by Junta de Castilla y León (Spain), cofunded by European Social Fund, for a postdoctoral contract. This work was funded by Ministerio de Economía y Competitividad (Spain, project CTQ2013-40476-R) and Junta de Castilla y León (Spain, project BU324U14). We also acknowledge The Foundation of Supercomputing Center of Castile and León (FCSCL, Spain), Computing and Advanced Technologies Foundation of Extremadura (CénitS, LUSITANIA Supercomputer, Spain) and Consortium of Scientific and Academic Services of Cataluña (CSUC, Spain) for providing supercomputing facilities. This work was also made possible by NPRP grant # 6-330-2-140 from the Qatar National Research Fund (a member of Qatar Foundation). We also thank Dr. J. T. Muya and A. Ceulemans (University of Richmond) for providing us the optimized structures of pristine B80. The statements made herein are solely the responsibility of the authors
Separation of aromatic hydrocarbons from alkanes using the ionic liquid 1-ethyl-3-methylimidazolium bis{(trifluoromethyl) sulfonyl} amide
The liquid-liquid equilibrium for the ternary system formed by hexane, benzene and the ionic liquid 1-ethyl-3-methylimidazolium bis
Ionic Liquid-Based Microemulsions in Catalysis
The design and properties of surface-active
ionic liquids that
are able to form stable microemulsions with heptane and water are
presented, and their promise as reaction media for thermomorphic palladium-catalyzed
cross-coupling reactions is demonstrated
Adsorption of choline benzoate ionic liquid on graphene, silicene, germanene and boron-nitride nanosheets: a DFT perspective
The adsorption of choline benzoate ([CH][BE]) ionic liquid (IL) on the surface of different hexagonal nanosheets has been studied using Density Functional Theory (DFT) methods. For this, the interaction mechanism, binding energies and electronic structure of [CH][BE] ionic liquid on four types of nanosheets, i.e., graphene, silicene, germanene and boron-nitride, were estimated and compared. The adsorption of [CH][BE] ionic liquid on different nanosheets is mainly featured by van der Waals forces, leading to strong benzoate ion–surface π-stacking. Likewise, there is also an important charge transfer from the anion to the sheet. The electronic structure analysis shows that Si- and Ge-based sheets lead to the largest changes in the HOMO and LUMO levels of choline benzoate. This paper provides new insights into the capability of DFT methods to provide useful information about the adsorption of ionic liquids on nanosheets and how ionic liquid features could be tuned through the adsorption on the suitable nanosheet.Ministerio de Economı´a y
Competitividad (Spain, project CTQ2013-40476-R) and Junta de
Castilla y León (Spain, project BU324U14)
FDI and Wages: Evidence from Firm-Level and Linked Employer-Employee Data in Hungary, 1986-2008
A review of ionic liquids in pharmaceutical microbiology: antimicrobial and antibiofilm reagents
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