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131.
John J. D'Amico Frederic G. Bollinger John J. Freeman 《Journal of heterocyclic chemistry》1986,23(1):101-104
The reaction of various potassium salts [RNHC(=S)SK, R = N(CH3)2, morpholino, piperidino, and hexahydro-1-(1H)-azepinyl] with 3-chloro-2,4-pentanedione in ethanol at 25–30° afforded the 1-acetylacetonyl substitutedaminodithiocarbamates 1–4 [RNHC(=S)SCH(COCH3)2]. Under refluxing conditions, the same reactants gave the heterocyclic compounds 5–8. Possible mechanism and supporting ir, nmr and mass spectral data are discussed. 相似文献
132.
Commercial interfaces for multidimensional gas chromatography (MDGC) are based either on a valve or a pneumatic switching between columns. Both exhibit significant drawbacks and only few suppliers exist. An extremely simple interface has been set up to overcome these limitations without requiring any pneumatic control or valves switching. This new MDGC design is based on the cryo-control of the analyte transfer from the first to the second column through two cool strands of a capillary. This technique is simple to implement and does not require any special column connections. Applications involve non-polar/polar phase combinations, as well as chiral analysis, hyphenation to a conventional mass spectrometer, and olfactometric detection. In contrast to conventional MDGC configuration, the present configuration allows the use of a single oven to operate both columns at different temperatures. 相似文献
133.
Stereospecific introduction of deuterium on the adamantane skeleton has been accomplished with LiAID(OCH3)3-CuI. 相似文献
134.
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
135.
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
136.
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
137.
138.
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
139.
140.