2568-33-4Relevant academic research and scientific papers
Microwave-assisted acid-induced formation of linker vacancies within Zr-based metal organic frameworks with enhanced heterogeneous catalysis
Liang, Yu,Li, Chenhui,Chen, Lanjun,Huo, Jia,Loubidi, Mohammed,Zhou, Yangyang,Liu, Yanbo
, p. 787 - 790 (2021)
Herein, we report a microwave-assisted acid-induced post-treatment method for the formation of linker vacancies within Zr-based metal organic frameworks (Zr-MOFs). The number of linker vacancies can be easily regulated with this method by changing the concentration of the HCl solution and the duration of microwave irradiation. The optimized defective UiO-66 showed higher linker defects with a higher specific surface area and thermal stability. The results of the catalytic cyclization of citronella showed that the Zr-MOFs with more defects exhibited enhanced catalytic performance. This work may provide a new method for the creation of defective MOFs with high activity and stability.
KINETICS AND MECHANISM OF THE HYDRATION OF THE EQUILIBRIUM MIXTURE OF 3-METHYL-1-BUTEN-3-OL AND 3-METHYL-2-BUTEN-1-OL WITH ISOPRENE IN AQUEOUS SOLUTIONS OF SULFURIC ACID
Ryabova, R. S.,Osipova, G. F.,Vinnik, M. I.
, p. 1021 - 1024 (1992)
The kinetic relationships of the hydration of an equilibrium mixture of 3-methyl-1-buten-1-ol (dimethylvinylcarbinol, DMVC) and 3-methyl-2-buten-1-ol (dimethylallyl alcohol, DMAA) with isoprene (C5H8) were investigated in aqueous solutions of sulfuric acid from 24.9 to 49.7percent at 25 deg C.Data were obtained on the mechanism of hydration of the equilibrium mixture of DMVC and DMAA with isoprene.Key words: Kinetic relationships, hydration mechanism, equilibrium mixture.
Conversion of Isobutene and Formaldehyde to Diol using Praseodymium-Doped CeO2 Catalyst
Zhang, Zhixin,Wang, Yehong,Lu, Jianmin,Zhang, Chaofeng,Wang, Min,Li, Mingrun,Liu, Xuebin,Wang, Feng
, p. 8248 - 8254 (2016)
Conversion of low-carbon olefins to higher alcohols or olefins via the formation of C-C bonds is an increasingly important topic. We herein report an example of converting isobutene and formaldehyde (38 wt % aqueous solution) to 3-methyl-1,3-butanediol (MBD), a precursor for isoprene. The reaction occurs through a Prins condensation-hydrolysis reaction over a praseodymium (Pr)-doped CeO2 catalyst. The best MBD yield (70%) is achieved over the Pr-doped CeO2 catalyst. Catalyst characterizations with high-angle annular dark field transmission electron microscopy (HAADF-TEM), pyridine adsorption infrared (IR) and Raman spectroscopy, and density functional theory (DFT) calculations show that the doped Pr is uniformly and highly dispersed in the CeO2 crystalline phase. In addition, the Pr doping creates more oxygen vacancy sites on CeO2 and thus enhances the Lewis acidity of the catalyst, which is responsible for the catalytic performance of the Pr-CeO2 catalyst. (Chemical Equation Presented).
The experimental detection of a retro-Prince reaction exemplified by a homogeneous acid-catalyzed decomposition of isopentenols
Ryabova, R. S.,Osipova, G. F.
, p. 311 - 313 (1994)
The occurence of the retro-Prince reaction in the transformations of an equilibrium mixture of 2-methyl-3-buten-2-ol and 3-methyl-2-buten-1-ol in 24.9percent-49percent aqueous sulfuric acid at 25 deg C has been experimentally proved. - Key words: acid catalysis; equilibrium mixture; isopentenols; Prince reaction.
Preparation method 3 -methyl -1-3 -butanediol
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Paragraph 0038; 0040-0041; 0043-0044; 0046-0047; 0049; ..., (2021/06/02)
The present invention relates to a preparation method of 3-methyl-1,3-butanediol. The method comprises the steps of mixing isobutene, a formaldehyde aqueous solution and a Pr-doped ceria catalyst, putting the mixture into a pressure-resistant container for sealing, and stirring for reacting to prepare the 3-methyl-1,3-butanediol by Prins condensation and hydrolysis. The separation process has theadvantages that the product and the catalyst are simple to separate, the catalyst can be recycled, the reaction process is simple, controllable and easy to operate, and the yield of the 3-methyl-1,3-butanediol is up to 98%.
Method for preparing 3 - methyl -1 and 3 - butanediol
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Paragraph 0037; 0039; 0040; 0042; 0043; 0045; 0046; ..., (2021/06/02)
The present invention relates to a preparation method of 3-methyl-1,3-butanediol. The 3-methyl-1,3-butanediol is prepared from isobutylene and a formaldehyde aqueous solution as reaction substrates byPrins condensation and hydrolysis process under the action of a doped ceria catalyst. A specific reaction process is as follows: a certain amount of the isobutylene, the formaldehyde aqueous solutionwith a certain concentration and a certain amount of the doped ceria catalyst are mixed and put into a container for sealing, stirring at temperature not lower than 60DEG C for reacting for 0.5h or more, and separating to obtain the 3-methyl-1,3-butanediol. The preparation method has the advantages that the product and the catalyst are simple to separate, the catalyst can be recycled, the reaction process is simple, controllable and easy to operate, and the yield of the 3-methyl-1,3-butanediol is up to 95%.
Rapid Deoxyfluorination of Alcohols with N-Tosyl-4-chlorobenzenesulfonimidoyl Fluoride (SulfoxFluor) at Room Temperature
Guo, Junkai,Kuang, Cuiwen,Rong, Jian,Li, Lingchun,Ni, Chuanfa,Hu, Jinbo
supporting information, p. 7259 - 7264 (2019/05/10)
The deoxyfluorination of alcohols is a fundamentally important approach to access alkyl fluorides, and thus the development of shelf-stable, easy-to-handle, fluorine-economical, and highly selective deoxyfluorination reagents is highly desired. This work describes the development of a crystalline compound, N-tosyl-4-chlorobenzenesulfonimidoyl fluoride (SulfoxFluor), as a novel deoxyfluorination reagent that possesses all of the aforementioned merits, which is rare in the arena of deoxyfluorination. Endowed by the multi-dimensional modulating ability of the sulfonimidoyl group, SulfoxFluor is superior to 2-pyridinesulfonyl fluoride (PyFluor) in fluorination rate, and is also superior to perfluorobutanesulfonyl fluoride (PBSF) in fluorine-economy. Its reaction with alcohols not only tolerates a wide range of functionalities including the more sterically hindered alcoholic hydroxyl groups, but also exhibits high fluorination/elimination selectivity. Because SulfoxFluor can be easily prepared from inexpensive materials and can be safely handled without special techniques, it promises to serve as a practical deoxyfluorination reagent for the synthesis of various alkyl fluorides.
The in situ transformation of the co-product formaldehyde in the reversible hydrolysis of 1,3-dixoane to obtain 1,3-propanediol efficiently
Wang, Yehong,Zhang, Jian,Zhang, Zhixin,Hou, Tingting,Zhang, Chaofeng,An, Jinghua,Wang, Feng
supporting information, p. 1455 - 1458 (2018/04/12)
Herein, a strategy is developed for efficient production of l,3-propanediol via the hydrolysis of 1,3-dioxane by the in situ transformation of the co-product formaldehyde (HCHO) in the presence of Eu(OH)3. The reversible hydrolysis reaction is promoted to yield 98% conversion and 99% 1,3-propanediol selectivity. Furthermore, HCHO is converted to formic acid (HCOOH) which could act as an acidic catalyst in the hydrolysis of 1,3-dioxane. The combination of FT-IR and control experiments demonstrates that HCOOH is generated via the hydrolysis of formate species which formed on the surface of Eu(OH)3.
Hydrogenation of CO2-Derived Carbonates and Polycarbonates to Methanol and Diols by Metal–Ligand Cooperative Manganese Catalysis
Zubar, Viktoriia,Lebedev, Yury,Azofra, Luis Miguel,Cavallo, Luigi,El-Sepelgy, Osama,Rueping, Magnus
supporting information, p. 13439 - 13443 (2018/09/21)
The first base-metal-catalysed hydrogenation of CO2-derived carbonates to alcohols is presented. The reaction proceeds under mild conditions in the presence of a well-defined manganese complex with a loading as low as 0.25 mol %. The non-precious-metal homogenous catalytic system provides an indirect route for the conversion of CO2 into methanol with the co-production of value-added (vicinal) diols in yields of up to 99 %. Experimental and computational studies indicate a metal–ligand cooperative catalysis mechanism.
METHOD FOR PRODUCING CONJUGATED DIENE
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Paragraph 0069-0074, (2018/10/30)
A method for producing a conjugated diene, including a step A of allowing an α-olefin and formaldehyde to react with each other to produce a γ,δ-unsaturated alcohol in the presence of an alcohol; and a step B of subjecting the γ,δ-unsaturated alcohol to a dehydration reaction at 135 to 210° C. in the presence of an aqueous solution of an acidic catalyst.
