C:Corrosive;
79-41-4Relevant articles and documents
Ni-Catalyzed enantioselective reductive arylcyanation/cyclization of: N -(2-iodo-aryl) acrylamide
Dong, Kaiwu,Ren, Xinyi,Shen, Chaoren,Wang, Guangzhu
supporting information, p. 1135 - 1138 (2022/02/03)
A Ni/(S,S)-BDPP-catalyzed intramolecular Heck cyclization of N-(2-iodo-aryl) acrylamide with 2-methyl-2-phenylmalononitrile was developed to give oxindoles with good enantioselectivities. We found that utilizing such an electrophilic cyanation reagent cou
A CATALYST AND A PROCESS FOR THE PRODUCTION OF ETHYLENICALLY UNSATURATED CARBOXYLIC ACIDS OR ESTERS
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Page/Page column 40, (2021/02/05)
The invention discloses a catalyst comprising a silica support, a modifier metal and a catalytic alkali metal. The silica support has a multimodal pore size distribution comprising a mesoporous pore size distribution having an average pore size in the range 2 to 50 nm and a pore volume of said mesopores of at least 0.1 cm3/g, and a macroporous pore size distribution having an average pore size of more than 50 nm and a pore volume of said macropores of at least 0.1 cm3/g. The level of catalytic alkali metal on the silica support is at least 2 mol%. The modifier metal is selected from Mg, B, Al, Ti, Zr and Hf. The invention also discloses a method of producing the catalyst, a method of producing an ethylenically unsaturated carboxylic acid or ester in the presence of the catalyst, and a process for preparing an ethylenically unsaturated acid or ester in the presence of the catalyst.
Method for synthesizing methacrylic acid by decarboxylating itaconic acid
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Paragraph 0043-0050, (2021/11/06)
The invention relates to a method for synthesizing methacrylic acid by decarboxylating itaconic acid. The method comprises the following steps: adding water, itaconic acid and a catalyst into a high-pressure kettle, sealing the high-pressure kettle, introducing nitrogen, and conducting reacting at 190-260 DEG C for 1-8 hours to obtain methacrylic acid, wherein the catalyst is a modified hydroxyapatite catalyst with a general formula of M10(ZO4)6(X) 2, M is one or two selected from a group consisting of Ca, Mg, Ba, Fe or Sr, ZO4 is PO4, and X is OH. The modified hydroxyapatite catalyst has the advantages of being high in activity and selectivity, easy to separate, environmentally friendly and the like, an itaconic acid conversion rate is larger than 98%, and the selectivity of the target product methacrylic acid can reach 75% or above at most.
Ligand-controlled divergent dehydrogenative reactions of carboxylic acids via C–H activation
Wang, Zhen,Hu, Liang,Chekshin, Nikita,Zhuang, Zhe,Qian, Shaoqun,Qiao, Jennifer X.,Yu, Jin-Quan
, p. 1281 - 1285 (2021/12/10)
Dehydrogenative transformations of alkyl chains to alkenes through methylene carbon-hydrogen (C–H) activation remain a substantial challenge. We report two classes of pyridine-pyridone ligands that enable divergent dehydrogenation reactions through palladium-catalyzed b-methylene C–H activation of carboxylic acids, leading to the direct syntheses of a,b-unsaturated carboxylic acids or g-alkylidene butenolides. The directed nature of this pair of reactions allows chemoselective dehydrogenation of carboxylic acids in the presence of other enolizable functionalities such as ketones, providing chemoselectivity that is not possible by means of existing carbonyl desaturation protocols. Product inhibition is overcome through ligand-promoted preferential activation of C(sp3)–H bonds rather than C(sp2)–H bonds or a sequence of dehydrogenation and vinyl C–H alkynylation. The dehydrogenation reaction is compatible with molecular oxygen as the terminal oxidant.
Supported Rb- or Cs-containing HPA catalysts for the selective oxidation of isobutane
Dumeignil, Franck,Katryniok, Benjamin,Paul, Sébastien,Zhang, Li
, (2021/10/29)
Silica-supported catalysts based on Keggin-type heteropolyacids (HPAs) containing rubidium or cesium as counter cations have been prepared by the impregnation method and evaluated in the selective oxidation of isobutane to methacrolein and methacrylic acid. The catalysts were characterized by various techniques such as XRD, N2 physisorption, TGA, Raman spectroscopy, H2-TPR, and NH3-TPD in order to study their thermal stability, structural, and textural properties, acidity and reducibility. It was evidenced that the reducibility of the Keggin type HPAs was improved by supporting the active phase on SiO2. A loading of 40 wt% was the optimum for the selective oxidation of isobutane (IBAN) to methacrylic acid (MAA). The selectivities to MAA and methacrolein (MAC) at given conversion were increased when Cs+ was used as counter cation compared to Rb+. The same trend was observed for mono- and di-vanado-substituted phosphomolybdic acid, whereby the performance followed the order: CsV1/SiO2 > RbV1/SiO2 > CsV2/SiO2 > RbV2/SiO2. The density of acid sites was correlated to the catalytic activity, which underlines the importance of the acid sites for alkane activation.
High-performance 3D printing UV-curable resins derived from soybean oil and gallic acid
Cheng, Jianwen,Hu, Lihong,Hu, Yun,Huang, Jia,Liu, Chengguo,Shang, Qianqian,Yu, Xixi,Zhang, Jinshuai,Zhou, Yonghong,Zhu, Guoqiang
, p. 5911 - 5923 (2021/08/23)
Developing sustainable 3D printing materials has attained intensive interest due to the rapid growth of the 3D printing industry and the concerns on depletion of fossil resources and environmental pollution. In this work, a novel biobased UV-curable oligomer (GMAESO) was firstly synthesized from epoxidized soybean oil (ESO) and gallic acid (GA) via a 'green' one pot method. The obtained biobased oligomer possessed a biobased content of 82.9%. By co-photopolymerization of the obtained oligomer with a hydroxyethyl methacrylate (HEMA) diluent, a series of UV-curable materials were prepared, and their properties as well as curing behaviors were investigated. Notably, the resulting GMAESO resins with high HEMA contents (50-60%) showed low viscosities (52-93 mPa s) and excellent thermal and mechanical properties (a Tg of 128-130 °C, Tp >430 °C, a tensile strength of 42.2-44.4 MPa, etc.) which were comparable or superior to a commercial product. Furthermore, the optimal resin (GMAESO with 50% HEMA) was used for digital light processing (DLP) 3D printing. The resin showed lower penetration depth (0.277 mm) than the commercial resin, thus different-structured objects with high resolution were successfully printed. In general, the developed bio-based UV-curable resins are very promising for application in the 3D printing industry.
Cobalt-catalyzed carboxylation of aryl and vinyl chlorides with CO2
Wang, Yanwei,Jiang, Xiaomei,Wang, Baiquan
supporting information, p. 14416 - 14419 (2020/12/01)
The transition-metal-catalyzed carboxylation of aryl and vinyl chlorides with CO2 is rarely studied, and has been achieved only with a Ni catalyst or combination of palladium and photoredox. In this work, the cobalt-catalyzed carboxylation of aryl and vinyl chlorides and bromides with CO2 has been developed. These transformations proceed under mild conditions and exhibit a broad substrate scope, affording the corresponding carboxylic acids in good to high yields.
PROCESS FOR PREPARING N-METHYL(METH)ACRYLAMIDE
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Page/Page column 5-6, (2020/02/16)
The invention relates to a process for preparing N-methyl(meth)acrylamide and to the uses thereof.
Macrolactam Synthesis via Ring-Closing Alkene-Alkene Cross-Coupling Reactions
Goh, Jeffrey,Loh, Teck-Peng,Maraswami, Manikantha
supporting information, p. 9724 - 9728 (2020/12/21)
Reported herein is a practical method for macrolactam synthesis via a Rh(III)-catalyzed ring closing alkene-alkene cross-coupling reaction. The reaction proceeded via a Rh-catalyzed alkenyl sp2 C-H activation process, which allows access to macrocyclic molecules of different ring sizes. Macrolactams containing a conjugated diene framework could be easily prepared in high chemoselectivities and Z,E stereoselectivities.
A PROCESS FOR THE PRODUCTION OF A CATALYST, A CATALYST THEREFROM AND A PROCESS FOR PRODUCTION OF ETHYLENICALLY UNSATURATED CARBOXYLIC ACIDS OR ESTERS
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Page/Page column 31-32, (2020/09/30)
The present invention relates to a process for producing a catalyst. The process comprises the steps of: a) providing an uncalcined metal modified porous silica support wherein the modifier metal is selected from one or more of boron, magnesium, aluminium, zirconium, hafnium and titanium, wherein the modifier metal is present in mono- or dinuclear modifier metal moieties; b) optionally removing any solvent or liquid carrier from the modified silica support; c) optionally drying the modified silica support; d) treating the uncalcined metal modified silica support with a catalytic metal to effect adsorption of the catalytic metal onto the metal modified silica support; and e) calcining the impregnated silica support of step d). The invention extends to an uncalcined catalyst intermediate and a method of producing a catalyst by providing a porous silica support having isolated silanol groups.
