554-14-3Relevant articles and documents
Conversion of 2-Methylfuran to 2-Methylthiophene over Molecular Sieves. Part 1. - Alkaline Y-Zeolites
Ferino, Italo,Monaci, Roberto,Solinas, Vincenzo,Oliva, Cesare,Pieri, Ilaria,Forni, Lucio
, p. 193 - 198 (1990)
The use of MeI Y zeolites (MeI = Li, Na, K, Rb, Cs) for the title reaction has been studied at 623 K and atmospheric pressure, looking at the effect of the nature of monovalent alkali-metal ions on both physico-chemical and catalytic properties of the resulting catalyst.The catalyst is very active and selective and, after ageing, it can be regenerated quite easily by a proper redox treatment.Besides the desired product, small amounts to traces of ca. 30 byproducts were detected, the structure of which can be explained only by admitting two different parallel reactions, one based on a ionic-type and the other on a radical-type mechanism.Some hypotheses are proposed on the possible start-up of such mechanisms, based on different adsorption modes of H2S onto the catalyst surface.
Gas-phase pyrolysis of thiopheneacetic acids, thienylethanols, and related compounds - Protophilicity of ring π-electrons and relative acidities of hydrogen-bond donors of hydroxyl groups
Al-Juwaiser, Ibtehal A.,Al-Awadi, Nouria A.,El-Dusouqui, Osman M.E.
, p. 499 - 503 (2002)
Based on kinetic data of thermal gas-phase elimination reactions, the following Arrhenius log A (s-1) and Ea (kJ mol-1) values, respectively, are obtained: 10.76 and 153.5 for 3-thiopheneacetic acid (1), 10.08 and 149.4 for 2-thiopheneacetic acid (2), 12.04 and 207.1 for 2-(3-thienyl)ethanol (3), 11.55 and 203.3 for 2-(2-thienyl)ethanol (4), 10.91 and 123.4 for 2-thiopheneglyoxylic acid (5), 11.05 and 223.8 for 1-(2-thienyl)propan-1-one (6), and 10.33 and 149.8 for 3-thiophenemalonic acid (7). The products of these pyrolytic reactions were either carbon dioxide or formaldehyde in addition to methylthiophene or thiophenecarboxaldehyde. Both positional and molecular reactivities of the substrates and related compounds are compared, and the results are rationalized on the basis of a reaction pathway involving a concerted six-membered transition state.
Iodine-catalyzed alcohol disproportionation method
-
Paragraph 0042-0043, (2021/06/13)
The invention relates to the technical field of catalysis, in particular to an iodine-catalyzed alcohol disproportionation method which comprises the following steps: sequentially adding alcohol, iodine and a solvent into a high-temperature and high-pressure reaction kettle, introducing a certain amount of nitrogen, conducting reacting for a certain time, collecting an organic phase after the reaction is ended, and conducting fractionating to obtain corresponding alkane and aldehyde/ketone. Alcohol disproportionation is efficient and atom-economical conversion without any additional oxidizing agent and reducing agent, and hydrocarbon and aldehyde/ketone molecules which are easy to separate can be formed at the same time. Meanwhile, the method has wide functional group tolerance, various substrate samples including aryl alcohol derivatives, heterocyclic alcohol derivatives, allyl alcohol derivatives and dihydric alcohol are tested, and the result shows that most of the substrate samples show good or extremely good yield.
On/Off O2 Switchable Photocatalytic Oxidative and Protodecarboxylation of Carboxylic Acids
Bazyar, Zahra,Hosseini-Sarvari, Mona
, p. 13503 - 13515 (2019/10/11)
Photoredox catalysis in recent years has manifested a powerful branch of science in organic synthesis. Although merging photoredox and metal catalysts has been a widely used method, switchable heterogeneous photoredox catalysis has rarely been considered. Herein, we open a new window to use a switchable heterogeneous photoredox catalyst which could be turned on/off by changing a simple stimulus (O2) for two opponent reactions, namely, oxidative and protodecarboxylation. Using this strategy, we demonstrate that Au@ZnO core-shell nanoparticles could be used as a switchable photocatalyst which has good catalytic activity to absorb visible light due to the localized surface plasmon resonance effect of gold, can decarboxylate a wide range of aromatic and aliphatic carboxylic acids, have multiple reusability, and are a reasonable candidate for synthesizing both aldehydes/ketones and alkane/arenes in a large-scale set up. Some biologically active molecules are also shown via examples of the direct oxidative and protodecarboxylation which widely provided pharmaceutical agents.