187737-37-7Relevant articles and documents
A ZEOLITE CATALYST AND USE THEREOF FOR THE DEHYDROGENATION OF ALKANES
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Page/Page column 29-31, (2022/02/05)
The present invention relates to a zeolite catalyst, wherein the zeolite catalyst comprises a zeolitic material, wherein the framework of the zeolitic material comprises Y02 and X203, wherein Y is a tetravalent element and X is a trivalent element, wherein the Y : X molar ratio of Y and X contained in the framework of the zeolitic material is comprised in the range of from 500 to 10,000, and wherein the zeolite catalyst further comprises Pt which is supported on the zeolitic material. Furthermore, the present invention relates to a molding comprising the zeolite catalyst, as well as to processes for the preparation of the molding. The present invention also relates to a process for the dehydrogenation of alkanes using the inventive zeolite catalyst or molding, as well as to their respective use. In particular, the catalyst can be Pt/ZSM-5, Pt-Zn/ZSM-5, Pt-K/ZSM-5 or Pt-Zn-K / ZSM-5, with the zeolite exhibiting a Si/A I molar ratio of 850.
TfO-···H-O-H Interaction-Assisted Generation of a Silicon Cation from Allylsilanes: Access to Phenylallyl Ferrier Glycosides from Glycals
Addanki, Rupa Bai,Halder, Suvendu,Kancharla, Pavan K.
supporting information, p. 1465 - 1470 (2022/02/23)
We demonstrate here that the strained and bulky protonated 2,4,6-tri-tert-butylpyridine (TTBPy) triflate salt serves as a mild and efficient organocatalyst for the diastereoselective C-Ferrier glycosylation of various glycals. The importance of the role of the 1/2 H2O molecule trapped in the catalyst has been disclosed. The mechanism of action involves unique anionic triflate and H2O hydrogen-bond interactions that assist the activation of allylsilanes, providing unprecedented access to diastereoselective phenylallyl Ferrier glycosides.
Impact of composition and structural parameters on the catalytic activity of MFI type titanosilicalites
Bruk, Lev,Chernyshev, Vladimir,Khramov, Evgeny,Kravchenko, Galina,Kustov, Aleksander,Kustov, Leonid,Kuz'Micheva, Galina,Markova, Ekaterina,Pastukhova, Zhanna,Pirutko, Larisa
, p. 3439 - 3451 (2022/03/14)
Titanosilicalite of the MFI type was obtained via a hydrothermal method. Its initial and annealed at 75 °C (TS-1P(75)) and 500 °C (TS-1P(500)) forms were studied by X-ray powder diffraction (PXRD), X-ray absorption spectroscopy (XAS-method), Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), temperature-programmed ammonia desorption (TPD NH3), and pyridine adsorption (Py). The full-profile Rietveld method allowed us to observe the presence of the organic template tetrapropylammonium hydroxide (TPAOH) in the framework voids, as well as to determine the silicate module (Si/Ti = 73.5) and the distribution of Ti4+ ions over the MFI-type structure sites (Ti atoms replace Si ones in two positions: T1 and T6). The coordination numbers of titanium (CNTi = 4.6 for TS-1P and TS-1P(75), CNTi = 3.8 for TS-1P(500)) were established by the XAS-method. The catalytic activity of titanosilicalites was found in the reactions of nitrous oxide decomposition (the maximal decomposition rate is demonstrated for the TS-1P(75) sample), allyl chloride epoxidation to epichlorohydrin (the best combination of all indicators was exhibited for the TS-1P sample) and propane conversion (maximum propane conversion, and butadiene and propylene selectivity were observed in both TS-1P(75) and TS-1P(500) samples). Mechanisms for the catalytic processes are proposed. The relationship between the catalytic properties and the composition (Si/Ti), Ti4+ ion distribution over the MFI-type structure sites, the local environment of titanium ions, and the number of acid sites in the titanosilicalites are discussed.
