A polymeric ionic liquid catalyst for the N-formylation and N-methylation of amines using CO2/PhSiH3
Journal of CO2 Utilization. 2020. Vol. 41. P. 101240.
Gopakumar A., Lombardo L., Fei Z., Shyshkanov S., Vasilyev D., Chidambaram A., Stylianou K., Züttel A., Dyson P.
We describe a polymeric ionic liquid (PIL) derived from trimethyl(p-vinylbenzyl)ammonium chloride ([VBTAm]Cl) that efficiently catalyzes the N-formylation of amines employing CO2 and PhSiH3 at room temperature with low catalyst loadings in near-quantitative yield. Under more forcing conditions N-methylated products can be selectively obtained. The PIL catalyst can be easily recovered and reused repeatedly without a decrease in activity. The reaction mechanism was studied in situ using high-pressure NMR spectroscopy and a tentative mechanistic cycle has been proposed.
Research target: Chemistry
Priority areas: engineering science
, , et al., Chemistry - A European Journal 2019 Vol. 25 No. 47 P. 11074-11079
N‐formylation of amines combining CO2 as a C1 source with a hydrosilane reducing agent is a convenient route for the synthesis of N‐formylated compounds. A large number of salts including ionic liquids (ILs) have been shown to efficiently catalyze the reaction and, yet, the key features of the catalyst remain unclear and the best salt catalysts ...
Added: October 29, 2020
, , et al., undefined 2018 Vol. 1 No. 10 P. 5124-5128
Pyrazolium ionic liquids (Pz ILs) were employed as co-catalysts for electrochemical conversion of CO2 to CO on a silver disk electrode, leading to a significant decrease in the onset potential for the reduction (ca. 500 mV). The electrochemical conversion of CO2 to CO proceeds in acetonitrile-based electrolytes containing Pz IL co-catalysts with Faradaic efficiencies (FEs) of nearly ...
Added: October 29, 2020
New Insights Into the Role of Imidazolium-Based Promoters for the Electroreduction of CO2 on a Silver Electrode
, , et al., Journal of the american chemical society 2016 Vol. 138 No. 25 P. 7820-7823
The electrochemical reduction of CO2 to CO is a reaction of central importance for sustainable energy conversion and storage. Herein, structure–activity relationships of a series of imidazolium-based cocatalysts for this reaction are described, which demonstrate that the C4- and C5-protons on the imidazolium ring are vital for efficient catalysis. Further investigation of these findings led to ...
Added: October 29, 2020
, , et al., undefined 2020 Vol. 3 No. 5 P. 4690-4698
Electrochemical reduction of carbon dioxide (CO2RR) is promoted by ionic liquid (IL) co-catalysts, and several mechanisms have been proposed to explain their role. Due to the complexity of the CO2RR and the limited number of active IL co-catalysts, a consensus on the precise role of ILs has not been reached, and it is not possible ...
Added: October 29, 2020
, , , Carbon 2021 Vol. 175 P. 202-214
Based on the quantum-mechanical theory of electron transfer (ET), the parameter was proposed to describe the electrochemical activity of doped graphenes. The parameter is calculated using the density of states (DOS), local density of state (LDOS) values, which are in turn obtained from the density functional theory (DFT) calculations and reorganization energies of redox system. ...
Added: January 12, 2021
, , et al., Electrochimica Acta 2018 Vol. 284 P. 346-354
We propose and develop a classical density functional theory for the description of a minor amount of water dissolved in ionic liquid in the vicinity of an electrode. In addition to the electrostatic energy and lattice-gas mixing entropy terms, the utilised grand canonical potential contains several phenomenological terms/parameters that describe short-range interactions between ions of ...
Added: August 3, 2018
Intricacies of Cation–Anion Combinations in Imidazolium Salt-Catalyzed Cycloaddition of CO2 Into Epoxides
, , et al., ACS Catalysis 2018 Vol. 8 No. 3 P. 2589-2594
The cycloaddition of CO2 into epoxides catalyzed by imidazolium and related salts continues to attract attention due to the industrial importance of the cyclic carbonate products. The mechanism of the imidazolium-catalyzed transformation has been proposed to require the participation of the acidic C2 proton. However, other simple salts without acidic protons, such as N,N,N,N-tetrabutylammonium chloride, are also ...
Added: October 29, 2020
A General and Facile Approach for the Electrochemical Reduction of Carbon Dioxide Inspired by Deep Eutectic Solvents
, , et al., ChemSusChem 2019 Vol. 12 No. 8 P. 1635-1639
Deep eutectic solvents (DESs) were applied to the electrochemical CO2 reduction reaction (CO2RR). Choline‐based DESs represent a non‐toxic and inexpensive alternative to room‐temperature ionic liquids (RTILs) as additives to the system or as electrolyte. Following the study on choline‐based DESs this approach was generalized and simple and organic‐soluble systems were devised based on the combination of ...
Added: October 29, 2020
Comparative Experimental and Theoretical Study of Mg, Al and Zn Aryloxy Complexes in Copolymerization of Cyclic Esters: The Role of the Metal Coordination in Formation of Random Copolymers
, , et al., Polymers 2020 Vol. 12 P. 2273
Homogeneity of copolymers is a general problem of catalytic coordination polymerization. In ring-opening polymerization of cyclic esters, the rational design of the catalyst is generally applied to solve this problem by the equalization of the reactivities of comonomers— however, it often leads to a reduction of catalytic activity. In the present paper, we studied the catalytic behavior of BnOH-activated ...
Added: October 28, 2020
, , , Journal of Physical Chemistry C 2021 Vol. 125 No. 38 P. 21151-21159
We formulate a general mean-field theory for a flat electric double layer in ionic liquids and electrolyte solutions with ions possessing static polarizability and a permanent dipole moment on a charged electrode. We establish a new analytical expression for electric double-layer differential capacitance, determining it as an absolute value of the ratio of the local ...
Added: September 16, 2021
Accessing Mononuclear Triphenylcyclopentadienyl Lanthanide Complexes by Using Tridentate Nitrogen Ligands: Synthesis, Structure, Luminescence, and Catalysis
, , et al., Organometallics 2021 Vol. 40 No. 9 P. 1235-1243
A series of mononuclear aryl-substituted cyclopentadienyl complexes [CpPh3LnCl2(Me3tach)] (Ln = Tb (4), Ln = Nd (5)), [CpPh2ArTbCl2(Me3tach)] (6), and [CpPh3LnCl2(Me3tacn)] (Ln = Tb (7), Ln = Nd (8), CpPh3: 1,2,4-triphenylcyclopentadienyl, CpPh2Ar: 1,2-diphenyl-4-(o-methoxyphenyl)cyclopentadienyl, Me3tach: 1,3,5-trimethyl-1,3,5-triazacyclohexane, Me3tacn: 1,4,7-trimethyl-1,4,7-triazacyclononane) have been synthesized from polynuclear precursors, using cyclic tridentate nitrogen-based ligands to prevent formation of ate complexes. All the obtained complexes have been ...
Added: June 26, 2021
, , et al., Journal of Alloys and Compounds 2021 Vol. 859 Article 157782
MgPd2 is an intermetallic compound with a reversible hydrogen uptake near ambient conditions. Hydrogenation occurs near room temperature at pressures below 0.1 MPa to form a hydrogen-rich MgPd2H0.88 phase. In this work, hydrogen sorption isotherms were measured at 283 K ≤ T ≤ 328 K as well as at a cryogenic temperature of 77 K and pressure values up ...
Added: November 5, 2020
, , et al., Физика и техника полупроводников 2017 Т. 51 № 8 С. 1028-1030
Thermoelements for thermoelectric coolers from fine-crystalline materials based on antimony and bismuth chalcogenide solid solutions of p- and n-type conductivities, obtained by hot pressing and extrusion from powders, made by melt spinning, were studied. Calculations of modules’ properties were performed in the range of 100−400K, taking into account temperature dependencies of thermoelectric parameters of legs, and the parameters of thermoelectric legs’ matching ...
Added: October 30, 2019
Издательский дом НИУ ВШЭ, 2019
Учебно-методическое пособие составлено на основании многолетнего опыта преподавания курса неорганической химии на химическом факультете МГУ имени М.В. Ломоносова. Пособие является руководством к лабораторным занятиям и состоит из четырех глав. В первой главе изложена техника безопасности проведения лабораторных работ, во второй — приводится описание основной химической посуды и приемов обращения с ней, а также правила обращения с реактивами. ...
Added: September 9, 2019
, , et al., Electrochimica Acta 2020 Vol. 351 P. 136465
A major challenge in the design of electrochemical biodevices is to achieve fast rates of electron exchange between proteins and electrodes. In this work, we show that a significant increase in the direct electron transfer rate between a graphite electrode and Tobacco Peroxidase takes place when a surface exposed leucine, located in the vicinity of ...
Added: July 22, 2020
, , et al., Chemistry - A European Journal 2020 Vol. 26 P. 12188-12193
Two novel cerium(IV) phosphates were obtained: cerium(IV) hydroxidophosphate, Ce(OH)PO4, and cerium(IV) oxidophosphate, Cе2O(PO4)2, which were shown to complement the classes of isostructural compounds M(OH)PO4 and R2O(PO4)2, where M = Th, U and R = Th, U, Np, Zr. Cе2O(PO4)2 oxidophosphate is formed by elimination of H2O from the crystal structure of Ce(OH)PO4 during its thermal ...
Added: July 2, 2020
, М. : ЛЕНАНД, 2020
Within the presented monograph for the first time statistical approaches, based on the self-consistent field theory, were presented for the theoretical description of the thermodynamic properties of the ion-molecular systems (electrolyte solutions, ionic liquids, dielectric polymers and metal-organic frameworks) in the bulk solution and at the interfaces with the account for their molecular structure. In ...
Added: November 18, 2019
, , et al., ChemistrySelect 2020 Vol. 5 No. 39 P. 12243-12249
Energetic compounds 1–6, consisting of one or two furazan rings linked by azo or azoxy bridges and one or two nitro‐NNO‐azoxy substituents, were synthesized by nitration of the corresponding tert‐butyl‐NNO‐azoxy precursors with NO2BF4. Novel methods for the synthesis of 3,4‐bis(tert‐butyl‐NNO‐azoxy)furazan (7) and bis‐4,4′‐(tert‐butyl‐NNO‐azoxy)‐3,3′‐azoxyfurazan (21) were elaborated. The nitro‐NNO‐azoxy compounds obtained display high calculated detonation performance (vD=8.07–9.40 km s−1 and PC‐J=27.4–43.4 GPa) that ...
Added: October 17, 2020
Novel anion exchange membrane with low ionic resistance based on chloromethylated/quaternized‐grafted polystyrene for energy efficient electromembrane processes
, , , Journal of Applied Polymer Science 2020 Vol. 137 No. 19 P. 48656
A novel anion-exchange membrane has been manufactured by chloromethylation and subsequent quaternization of polystyrene within a graft copolymer films based on UV-oxidized polymethylpentene. Particular attention is given to the kinetics of chloromethylation and the influence of the reaction conditions on the properties of the anion-exchange membranes. By means of variation of the polystyrene content and ...
Added: February 27, 2020
Structure of the carboxypeptidase B complex with N-sulfamoyl-L-phenylalanine - a transition state analog of non-specific substrate
, , et al., Journal of Biomolecular Structure and Dynamics 2018 Vol. 36 No. 4 P. 956-965
Carboxypeptidase B (EC 18.104.22.168) (CPB) is commonly used in the industrial insulin production and as a template for drug design. However, its ability to discriminate substrates with hydrophobic, hydrophilic, and charged side chains is not well understood. We report structure of CPB complex with a transition state analog N-sulfamoyl-L-phenylalanine solved at 1.74 angstrom. The study ...
Added: January 28, 2019
Development of surface-sulfonated graft anion-exchange membranes with monovalent ion selectivity and antifouling properties for electromembrane processes
, , Journal of Membrane Science 2020 Vol. 612 P. 118408
This communication describes the development of anion-exchange membrane (AEM) with a modified surface possessing monovalent ion selectivity and antifouling properties. Modified AEMs series was obtained by the formation of an oppositely-charged thin layer utilizing the surface sulfonation of the grafted AEMs. The creation of the interface layer leads to a significant increase in the Cl/SO4 ...
Added: August 30, 2020
Bari : Digilabs Pub., 2021
ASYS, the AIPEA School for Young Scientists. ASYS was successfully convened at the Andalusian Institute of Earth Sciences (CSIC-UGR, Granada, Spain) on July 15 and 16, 2017, under the supervision of Dr. Claro Ignacio Sainz Díaz, researcher of this centre, and in close connection to the 16th International Clay Conference in Granada (ICC 2017). Young and not so-young ...
Added: September 5, 2021
, , , Mendeleev Communications 2018 Vol. 28 No. 2 P. 113-122
Carbon monoxide as an example of reducing agent, in contrast to classical reducing agents (hydrogen and metal hydrides), can provide very high atom precision for reductive addition of substrates with various functional groups. This enables synthesis of new compounds with unique structures and properties. ...
Added: June 26, 2019
Computation of drug solvation free energy in supercritical CO2: alternatives to all-atom computer simulations
, , et al., Fluid Phase Equilibria 2021 Vol. 544-545 Article 113096
Despite the modern level of development of computational chemistry methods and technological progress, fast and accurate determination of solvation free energy remains a huge problem for physical chemists. In this paper, we describe two computational schemes that can potentially solve this problem. We consider systems of poorly soluble drug compounds in supercritical carbon dioxide. Considering that the biggest contribution ...
Added: June 1, 2021