Scan Science and Technology
Contact Leading Edge Experts & Companies
The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Francis Verpoort – 1st expert on this subject based on the ideXlab platform
Alkyl Group tagged ruthenium indenylidene complexes synthesis characterization and metathesis activityJournal of Organometallic Chemistry, 2015Co-Authors: Baoyi Yu, Francis Verpoort, Fatma B Hamad, Karen Leus, A A Lyapkov, Kristof Van HeckeAbstract:
Abstract We report on the synthesis of ruthenium indenylidene catalysts [RuCl2(3-R-1-indenylidene)(PCy3)2 in which R is iso-propyl (7a), tert-butyl (7b) or cyclohexyl (7c)]. The obtained Alkyl tagged indenylidene catalysts were analyzed by means of IR, elemental analysis, NMR and single crystal X-Ray diffraction analysis. Furthermore, the catalytic performance of these new complexes was examined in different metathesis reactions: ring-closing metathesis (RCM), ring-closing ene-yne metathesis (RCEYM), ring-opening metathesis polymerization (ROMP) and cross metathesis (CM), exhibiting a comparable activity in comparison with the commercially available catalyst 3a.
Kervin O. Evans – 2nd expert on this subject based on the ideXlab platform
Room-temperature ionic liquid cations act as short-chain surfactants and disintegrate a phospholipid bilayerColloids and Surfaces A: Physicochemical and Engineering Aspects, 2006Co-Authors: Kervin O. EvansAbstract:
The effect of room-temperature ionic liquids (RT-ILs) cations made of 1-Alkyl-3-methylimidazolium (Alkyl Group of C4C8) and anions (commonly found in RT-ILs) on the structural integrity of large unilamellar vesicles (LUVs) of 1,2-dielaidoylphosphocholine were studied. Vesicle integrity was determined by monitoring the release of calcein quenched by cobalt ions and vesicle size distribution after incubation in the presences of each cation or anion. Results demonstrated that the instability of a fluid bilayer increased as the length of Alkyl Group of the cation increased. LUVS were mostly stable in the presence of the anions as evidenced by continued retention of encapsulated materials. Size measurements revealed, in the case of 1-butyl-3-methylimidazolium cation (100-1500 mM), encapsulated material was released through small holes in the bilayer. However, total vesicle disruption was the release mechanism in the case of 1-hexyl or octyl-3-methylimidazolium above 200 mM. © 2005 Elsevier B.V. All rights reserved.
Richard A Bartsch – 3rd expert on this subject based on the ideXlab platform
influence of structural variation in room temperature ionic liquids on the selectivity and efficiency of competitive alkali metal salt extraction by a crown etherAnalytical Chemistry, 2001Co-Authors: Sangki Chun, And Sergei V Dzyuba, Richard A BartschAbstract:
An improved method for the preparation of 1-Alkyl-3-methylimidazolium hexafluorophosphates provides a series of room-temperature ionic liquids (RTILs) in which the 1-Alkyl Group is varied systematically from butyl to nonyl. For competitive solvent extraction of aqueous solutions of alkali metal chlorides with solutions of dicyclohexano-18-crown-6 (DC18C6) in these RTILs, the extraction efficiency generally diminished as the length of the 1-Alkyl Group was increased. Under the same conditions, extraction of alkali metal chlorides into solutions of DC18C6 in chloroform, nitrobenzene, and 1-octanol was undetectable. The extraction selectivity order for DC18C6 in the RTILs was K+ > Rb+ > Cs+ > Na+ > Li+. As the Alkyl Group in the RTIL was elongated, the K+/Rb+ and K+/Cs+ selectivities exhibited general increases with the larger enhancement for the latter. For DC18C6 in 1-octyl-3-methylimidazolium hexafluorophosphate, the alkali metal cation extraction selectivity and efficiency were unaffected by variation of…