- Computational design of metal-organic frameworks based on stable zirconium building units for storage and delivery of methane
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A metal-organic framework (MOF) with high volumetric deliverable capacity for methane was synthesized after being identified by computational screening of 204 hypothetical MOF structures featuring (Zr6O4)(OH)4(CO2)n inorganic building blocks. The predicted MOF (NU-800) has an fcu topology in which zirconium nodes are connected via ditopic 1,4-benzenedipropynoic acid linkers. Based on our computer simulations, alkyne groups adjacent to the inorganic zirconium nodes provide more efficient methane packing around the nodes at high pressures. The high predicted gas uptake properties of this new MOF were confirmed by high-pressure isotherm measurements over a large temperature and pressure range. The measured methane deliverable capacity of NU-800 between 65 and 5.8 bar is 167 cc(STP)/cc (0.215 g/g), the highest among zirconium-based MOFs. High-pressure uptake values of H2 and CO2 are also among the highest reported. These high gas uptake characteristics, along with the expected highly stable structure of NU-800, make it a promising material for gas storage applications. (Figure Presented).
- Gomez-Gualdron, Diego A.,Gutov, Oleksii V.,Krungleviciute, Vaiva,Borah, Bhaskarjyoti,Mondloch, Joseph E.,Hupp, Joseph T.,Yildirim, Taner,Farha, Omar K.,Snurr, Randall Q.
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- Method for synthesizing acetylenic acid by using terminal alkyne and carbon dioxide
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The invention belongs to the field of organic synthesis, and particularly relates to a method for synthesizing acetylenic acid by using terminal alkyne and carbon dioxide. The method comprises the experimental steps that alkyne, alkali and a solvent are added into a reaction tube, the alkyne serves as a raw material, the alkali and the solvent provide a strong alkaline environment, CO2 is introduced into a reaction container to form a carbon dioxide atmosphere, heating and stirring reaction are carried out, after the reaction is finished, cooling is carried out to the room temperature, extraction and liquid separation are carried out, a water layer is acidified, then separation and purification are further carried out, and the acetylenic acid compound is obtained. The method is carried out under the conditions of low temperature and normal pressure, does not need to add a metal catalyst, is single in product and convenient to separate, good in substrate applicability and safe and simple to operate, and has potential industrial application prospects and good economic benefits.
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Paragraph 0151-0159
(2021/07/24)
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- Silver Nanoparticles Architectured HMP as a Recyclable Catalyst for Tetramic Acid and Propiolic Acid Synthesis through CO2 Capture at Atmospheric Pressure
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The recent advancement on the tailored synthesis of hypercrosslinked microporous polymer (HMP-2) has assembled significant concentration by the virtue of its adjustable porosity, operative design and absolutely ordering structure. This perfectly structured Ag NPs supported carbocatalyst (Ag-HMP-2) has been synthesized by Friedel-Crafts alkylation between 4,4′-Bis(bromomethyl)-1,1′-biphenyl and carbazole over anhydrous iron(III)chloride catalysis followed by the appending of the silver nanoparticles (Ag NPs) onto the material. The silver nanoparticle was decorated over the HMP-2 to prepare the corresponding catalyst (Ag-HMP-2). The characterization of the newly produced material has been conducted by N2 adsorption/desorption studies, XPS, FE-SEM, transmission electron microscopy (TEM) and Powder X-ray diffraction (PXRD) methods. This microporous catalyst has spectacular activities for the production of tetramic acids from various types of propargylic amine derivatives at 60 °C under atmospheric carbon dioxide pressure. Parallel attempt on fixation of CO2 was executed over terminal alkynes to synthesize propiolic acids under 1 atm pressure. The catalyst (Ag-HMP-2) exhibited sufficient recycling ability for the generation of tetramic acids and propiolic acids up to five catalytic runs without reduction in its catalytic activity.
- Ghosh, Swarbhanu,Ghosh, Aniruddha,Riyajuddin, Sk,Sarkar, Somnath,Chowdhury, Arpita Hazra,Ghosh, Kaushik,Islam, Sk. Manirul
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p. 1055 - 1067
(2020/01/21)
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- Carboxylation of terminal alkynes promoted by silver carbamate at ambient pressure
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Transition metal carbamates constitute a class of compounds with unique properties, however their catalytic potential has been sparingly explored so far. The easily available silver N,N-dimethylcarbamate, Ag(O2CNMe2), worked as a catalyst in the carboxylation reaction of terminal alkynes with CO2 at atmospheric pressure. Different reaction parameters (solvent, base, temperature, time and the amount of catalyst) were investigated in order to establish the optimal conditions.
- Bresciani, Giulio,Marchetti, Fabio,Pampaloni, Guido
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p. 10821 - 10825
(2019/07/15)
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- Sequential protocol for C(sp)–H carboxylation with CO2: KOtBu-catalyzed C(sp)–H silylation and KOtBu-mediated carboxylation
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CO2 incorporation into C–H bonds is an important and interesting topic. Herein a sequential protocol for C(sp)–H carboxylation by employing a metal-free C–H activation/catalytic silylation reaction in conjunction with KOtBu-mediated carboxylation with CO2 was established, in which KOtBu catalyzes silylation of terminal alkynes to form alkynylsilanes at low temperature, and simultaneously mediates carboxylation of the alkynesilanes with atmospheric CO2. Importantly, the carboxylation further promotes the silylation, which makes the whole reaction proceed very rapidly. Moreover, this methodology is simple and scalable, which is characterized by short reaction time, wide substrate scope, excellent functional-group tolerance and mild reaction conditions, affording a range of corresponding propiolic acid products in excellent yields in most cases. In addition, it also allows for a convenient 13C-labeling through the use of 13CO2.
- Yu, Bo,Yang, Peng,Gao, Xiang,Yang, Zhenzhen,Zhao, Yanfei,Zhang, Hongye,Liu, Zhimin
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p. 449 - 456
(2018/02/06)
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- Method for preparing propiolic acid and derivatives thereof under mild condition
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The invention provides a novel method for preparing propiolic acid compounds through a domino reaction. The method comprises a step of subjecting terminal alkyne compounds, hydrosilane and CO2 to thedomino reaction under the catalysis action of Lewis base so as to obtain propiolic acid compounds. According to the invention, common Lewis base is used as a promoter, and corresponding propiolic acidcompounds containing different function groups can be efficiently produced through a reaction of the terminal alkyne compounds with hydrosilane and normal-pressure CO2 under a mild condition (a temperature of 40 DEG D). According to the method, CO2 is used as a raw material; the cheap Lewis base is used as the promoter; usage of precious metals is avoided; the domino reaction is employed; purification and separation of intermediates are not needed; and reaction conditions are mild. Thus, the method is an efficient cheap green synthetic method and has good industrial application value.
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Paragraph 0155; 0156
(2018/09/08)
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- Flower-like AgNPs@m-MgO as an excellent catalyst for CO2 fixation and acylation reactions under ambient conditions
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Synthesis of fine chemicals from the chemical fixation of CO2 is one of the attractive research areas of today to utilise greenhouse gas CO2 in a greener pathway. A flower-like silver nanoparticle grafted mesoporous magnesium oxide (AgNPs@m-MgO) nanocomposite has been prepared by a facile in situ pathway. The materials are characterised by XRD, FTIR, UV-vis, TG-DTA, FESEM, HR-TEM and N2 adsorption-desorption studies. This AgNPs@m-MgO material showed a mesoporous nature with good surface area. It indicated brilliant catalytic activity for both the carboxylation of terminal alkynes by chemical fixation of CO2 (1 atm) and the acylation of various amines by utilizing acetic acid as a reagent in solvent-free conditions showing yields up to 98% and 99% of the propiolic acid and acetamide products, respectively. The reusability of this catalyst has also been verified and it showed high recycling efficiency for both the reactions together with no considerable catalyst deactivation.
- Chowdhury, Arpita Hazra,Ghosh, Swarbhanu,Islam, Sk. Manirul
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p. 14194 - 14202
(2018/08/28)
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- CsF-promoted carboxylation of aryl(hetaryl) terminal alkynes with atmospheric CO2 at room temperature
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A CsF-promoted carboxylation of aryl(hetaryl) terminal alkynes with atmospheric CO2 in the presence of trimethylsilylacetylene was developed to give functionalized propiolic acid products at room temperature. A wide range of propiolic acids bearing functional groups was successfully obtained in good to excellent yields. Mechanistic studies demonstrate that in the carboxylation process the alkynylsilane intermediate was first in situ generated, which was then trapped by CO2, giving rise to the corresponding functionalized propiolic acids after acidification. The advantages of this approach include avoiding use of transition-metal catalysts, wide substrate scope together with excellent functional group tolerance, ambient conditions and a facile work-up procedure.
- Yu,Yang,Gao,Yang,Zhao,Zhang,Liu
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supporting information
p. 9250 - 9255
(2017/08/29)
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- Method for preparing propiolic acid compounds
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The invention discloses a method for preparing propiolic acid compounds. An ionic type iron (III) complex containing monoimide functionalized imidazolium cations is taken as the single-component catalyst, carbon dioxide is taken as the carboxylation reagent, and various propiolic acid compounds are prepared through carboxylation reaction of terminal alkyne under normal pressure. The terminal alkyne substrate relates to phenylacetylene, substituted phenylacetylene, heterocyclic aryne, aromatic diyne or aliphatic series terminal alkyne. The method for preparing the propiolic acid compounds through carboxylation reaction of terminal alkyne and carbon dioxide under the catalysis of the iron-based catalyst is provided for the first time. Compared with the prior art, the method has the advantages that the catalyst is more environmentally friendly, synthesis is easier, reaction conditions are mild, and catalytic activity and functional group tolerance are unchanged or improved.
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Paragraph 0042; 0043
(2016/10/10)
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- Carboxylation of terminal alkynes with CO2 catalyzed by bis(amidate) rare-earth metal amides
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Three novel bis(amidate) rare-earth metal amides {LRE[N(SiMe3)2]·THF}2 (H2L = N,N′-(cyclohexane-1,2-diyl)bis(4-tert-butylbenzamide); RE = La(1), Nd(2), Y(3)), which were prepared by the treatment of the bridged amide proligand H2L with RE[N(SiMe3)2]3 in tetrahydrofuran, have been characterized by single-crystal X-ray diffraction, elemental analyses, and NMR for complexes 1 and 3. All the complexes were found, for the first time, to be efficient catalysts for the direct carboxylation of terminal alkynes with CO2 at ambient pressure. And the Nd-based catalyst 2 showed the highest reactivity. Various propiolic acids with a good functional group tolerance were successfully synthesized in high-to-excellent yields under mild conditions. This journal is
- Cheng, Hao,Zhao, Bei,Yao, Yingming,Lu, Chengrong
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p. 1675 - 1682
(2015/03/18)
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- Cycloaddition-based formal C-H alkynylation of isoindoles leading to the synthesis of air-stable fluorescent 1,3-dialkynylisoindoles
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Reaction of N-alkylisoindoles with (bromoethynyl)triisopropylsilane afforded 1,3-bis(triisopropylsilylethynyl) isoindoles in high yields. The formal C-H alkynylation proceeds under transition-metal-free conditions through [4 + 2] cycloaddition of the pyrrole ring of isoindole with bromoalkyne followed by ring-opening of the product.
- Ohmura, Toshimichi,Kijima, Akihito,Komori, Yusuke,Suginome, Michinori
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supporting information
p. 3510 - 3513
(2013/08/23)
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