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131.
Stereospecific introduction of deuterium on the adamantane skeleton has been accomplished with LiAID(OCH3)3-CuI. 相似文献
132.
Frederic Meunier 《催化学报》2019,(1)
正In a recent contribution [1] to this journal, Guo and co-workers reported on the design of a dual beam FT-IR spectrometer system aiming, among others, at totally removing the contribution of gas-phase species during operando studies of heterogeneous catalytic reactions. The system consists of two identical cells located in two separate FT-IR spectrometers, one being loaded with a catalyst wafer and the other one being 相似文献
133.
Kristian Torbensen Kristoffer Malmos Dr. Frederic Kanoufi Prof. Dr. Catherine Combellas Dr. Steen U. Pedersen Prof. Dr. Kim Daasbjerg 《Chemphyschem》2012,13(14):3303-3307
Scanning electrochemical microscopy is used to carry out local free‐radical grafting at a gold surface through mild oxidation of an aryl hydrazine. The process can be deliberately controlled by creation of a local pH gradient at the tip. Comparison of the experimental results with simulations shows that the radial expansion of the pH profile in which successful grafting can be accomplished increases with increasing generation time of OH? and with decreasing initial concentration of the grafting precursor. Furthermore, the radial expansion is faster than the nucleation of the grafting process. 相似文献
134.
Raphaël Frdrick Bernadette Norberg Franois Durant Frederic Ooms Johan Wouters 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):o623-o626
The structures of three compounds, namely 7‐methoxy‐2‐[3‐(trifluoromethyl)phenyl]‐9H‐indeno[1,2‐c]pyridazin‐9‐one, C19H11F3N2O2, (Id), 6‐methoxy‐2‐[3‐(trifluoromethyl)phenyl]‐9H‐indeno[1,2‐c]pyridazin‐9‐one, C19H11F3N2O2, (IId), and 2‐methyl‐6‐(4,4,4‐trifluorobutoxy)‐9H‐indeno[1,2‐c]pyridazin‐9‐one, C16H13F3N2O2, (IIf), which are potent reversible type‐B monoamine oxidase (MAO‐B) inhibitors, are presented and discussed. Compounds (Id) and (IId) crystallize in a nearly planar conformation. The crystal structures are stabilized by weak C—H⋯O hydrogen bonds. The packing is dominated by π–π stacking interactions between the heterocyclic central moieties of centrosymmetrically related molecules. In compound (IIf), the trifluoroethyl termination is almost perpendicular to the plane of the ring. 相似文献
135.
136.
Amina Khettabi Arkadiusz Grempka Dr. Frederic Lafolet Elarbi Chatir Dr. Nicolas Leconte Dr. Marie-Noelle Collomb Dr. Damien Jouvenot Dr. Saioa Cobo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(59):13359-13362
A pyridinium substituted dithienylethene derivative was used for the first time as an efficient photoreducing agent of two different substrates. This reaction exhibits high catalytic yields due to the continuous regeneration of the initial state of the photochromic molecule. 相似文献
137.
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139.
Cong X Czerwieniec G McJimpsey E Ahn S Troy FA Lebrilla CB 《Journal of the American Society for Mass Spectrometry》2006,17(3):442-452
Gas-phase zwitterionic amino acids were formed in complexes of underivatized beta-cyclodextrin through reactions with a neutral base, n-propylamine. The reaction was performed in the analyzer cell of an electrospray ionization-Fourier transform mass spectrometer. Most of the natural amino acids were studied with three cyclodextrin hosts including alpha-, beta-, and gamma-cyclodextrin to understand better the structural features that lead to the stabilization of the zwitterionic complexes. Molecular dynamics calculations were performed to provide insight into the structural features of the complexes. The rate constants of the reactions were obtained through kinetic plots. Examination of both L- and D-enantiomers of the amino acid showed that the reaction was enantioselective. The reaction was then employed to analyze mixtures of Glu enantiomers naturally occurring in the bacteria Bacillus licheniformis. 相似文献
140.
A novel potential ligand has been designed where two beta-dialdimine units are linked by a xanthene backbone (H2Xanthdim). The synthesis proceeds via a double vinamidinium salt and the products of its hydrolysis (containing eneamine/malonaldehyde units), which were converted into H2Xanthdim via a reaction with 2,3-dimethylaniline. The reaction of H2Xanthdim with n-butyllithium yields ((Et2O)Li)2Xanthdim, which was isolated and crystallized. The crystal structures of both H2Xanthdim and its lithium salt are discussed. 相似文献