1
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Nag P, Ranković M, Polášek M, Čurík R, Slaughter DS, Fedor J. Contrasting Dynamics in Isoelectronic Anions Formed by Electron Attachment. J Phys Chem Lett 2024; 15:895-902. [PMID: 38241169 PMCID: PMC10839900 DOI: 10.1021/acs.jpclett.3c03460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 01/09/2024] [Accepted: 01/12/2024] [Indexed: 01/21/2024]
Abstract
Cyanogen NCCN and cyanoacetylene HCCCN are isoelectronic molecules, and as such, they have many similar properties. We focus on the bond cleavage in these induced by the dissociative electron attachment. In both molecules, resonant electron attachment produces CN- with very similar energy dependence. We investigate the very different dissociation dynamics, in each of the two molecules, revealed by velocity map imaging of this common fragment. Different dynamics are manifested both in the excess energy partitioning and in the angular distributions of fragments. Based on the comparison with electron energy loss spectra, which provide information about possible parent states of the resonances (both optically allowed and forbidden excited states of the neutral target), we ascribe the observed effect to the distortion of the nuclear frame during the formation of core-excited resonance in cyanoacetylene. The proposed mechanism also explains a puzzling difference in the magnitude of the CN- cross section in the two molecules which has been so far unexplained.
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Affiliation(s)
- P. Nag
- J.
Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech
Republic
| | - M. Ranković
- J.
Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech
Republic
| | - M. Polášek
- J.
Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech
Republic
| | - R. Čurík
- J.
Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech
Republic
| | - D. S. Slaughter
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - J. Fedor
- J.
Heyrovský Institute of Physical Chemistry, The Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech
Republic
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2
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Shiels OJ, Marlton SJP, Poad BLJ, Blanksby SJ, da Silva G, Trevitt AJ. Gas-Phase Phenyl Radical + O 2 Reacts via a Submerged Transition State. J Phys Chem A 2024; 128:413-419. [PMID: 38174881 DOI: 10.1021/acs.jpca.3c06878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
In the gas-phase chemistry of the atmosphere and automotive fuel combustion, peroxyl radical intermediates are formed following O2 addition to carbon-centered radicals which then initiate a complex network of radical reactions that govern the oxidative processing of hydrocarbons. The rapid association of the phenyl radical-a fundamental radical related to benzene-with O2 has hitherto been modeled as a barrierless process, a common assumption for peroxyl radical formation. Here, we provide an alternate explanation for the kinetics of this reaction by deploying double-hybrid density functional theory (DFT), at the DSD-PBEP86-D3(BJ)/aug-cc-pVTZ level of theory, and locate a submerged adiabatic transition state connected to a prereaction complex along the reaction entrance pathway. Using this potential energy scheme, experimental rate coefficients k(T) for the addition of O2 to the phenyl radical are accurately reproduced within a microcanonical kinetic model. This work highlights that purportedly barrierless radical oxidation reactions may instead be modeled using stationary points, which in turn provides insight into pressure and temperature dependence.
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Affiliation(s)
- Oisin J Shiels
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong 2522, Australia
| | - Samuel J P Marlton
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong 2522, Australia
| | - Berwyck L J Poad
- School of Chemistry and Physics and the Central Analytical Research Facility, Queensland University of Technology, Brisbane 4001, Australia
| | - Stephen J Blanksby
- School of Chemistry and Physics and the Central Analytical Research Facility, Queensland University of Technology, Brisbane 4001, Australia
| | - Gabriel da Silva
- Department of Chemical Engineering, the University of Melbourne, Melbourne 3010, Victoria, Australia
| | - Adam J Trevitt
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong 2522, Australia
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3
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Neumark DM. Spectroscopy of Radicals, Clusters, and Transition States Using Slow Electron Velocity-Map Imaging of Cryogenically Cooled Anions. J Phys Chem A 2023; 127:4207-4223. [PMID: 37094039 DOI: 10.1021/acs.jpca.3c01537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Slow electron velocity-map imaging of cryogenically cooled anions (cryo-SEVI) is a high-resolution variant of anion photoelectron spectroscopy that has been applied with considerable success over the years to the study of radicals, size-selected clusters, and transition states for unimolecular and bimolecular reactions. Cryo-SEVI retains the versatility of conventional anion photoelectron spectroscopy while offering sub-meV resolution, thereby enabling the resolution of vibrational structure in the photoelectron spectra of complex anions. This Feature Article describes recent experiments in our laboratory using cryo-SEVI, including a new research direction in which anions are vibrationally pre-excited with an infrared laser pulse prior to photodetachment.
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Affiliation(s)
- Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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4
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Hu C, Mena J, Alabugin IV. Design principles of the use of alkynes in radical cascades. Nat Rev Chem 2023:10.1038/s41570-023-00479-w. [PMID: 37117812 DOI: 10.1038/s41570-023-00479-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/17/2023] [Indexed: 03/30/2023]
Abstract
One of the simplest organic functional groups, the alkyne, offers a broad canvas for the design of cascade transformations in which up to three new bonds can be added to each of the two sterically unencumbered, energy-rich carbon atoms. However, kinetic protection provided by strong π-orbital overlap makes the design of new alkyne transformations a stereoelectronic puzzle, especially on multifunctional substrates. This Review describes the electronic properties contributing to the unique utility of alkynes in radical cascades. We describe how to control the selectivity of alkyne activation by various methods, from dynamic covalent chemistry with kinetic self-sorting to disappearing directing groups. Additionally, we demonstrate how the selection of reactive intermediates directly influences the propagation and termination of the cascade. Diverging from a common departure point, a carefully planned reaction route can allow access to a variety of products.
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5
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The Electronic Nature of Cationic Group 10 Ylidyne Complexes. INORGANICS 2023. [DOI: 10.3390/inorganics11030129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2023] Open
Abstract
We report a broad theoretical study on [(PMe3)3MER]+ complexes, with M = Ni, Pd, Pt, E = C, Si, Ge, Sn, Pb, and R = ArMes, Tbb, (ArMes = 2,6-dimesitylphenyl; Tbb = C6H2-2,6-[CH(SiMe3)2]2-4-tBu). A few years ago, our group succeeded in obtaining heavier homologues of cationic group 10 carbyne complexes via halide abstraction of the tetrylidene complexes [(PMe3)3M=E(X)R] (X = Cl, Br) using a halide scavenger. The electronic structure and the M-E bonds of the [(PMe3)3MER]+ complexes were analyzed utilizing quantum-chemical tools, such as the Pipek–Mezey orbital localization method, the energy decomposition analysis (EDA), and the extended-transition state method with natural orbitals of chemical valence (ETS-NOCV). The carbyne, silylidyne complexes, and the germylidyne complex [(PMe3)3NiGeArMes]+ are suggested to be tetrylidyne complexes featuring donor–acceptor metal tetrel triple bonds, which are composed of two strong π(M→E) and one weaker σ(E→M) interaction. In comparison, the complexes with M = Pd, Pt; E = Sn, Pb; and R = ArMes are best described as metallotetrylenes and exhibit considerable M−E−C bending, a strong σ(M→E) bond, weakened M−E π-components, and lone pair density at the tetrel atoms. Furthermore, bond cleavage energy (BCE) and bond dissociation energy (BDE) reveal preferred splitting into [M(PMe3)3]+ and [ER] fragments for most complex cations in the range of 293.3–618.3 kJ·mol−1 and 230.4–461.6 kJ·mol−1, respectively. Finally, an extensive study of the potential energy hypersurface varying the M−E−C angle indicates the presence of isomers with M−E−C bond angles of around 95°. Interestingly, these isomers are energetically favored for M = Pd, Pt; E = Sn, Pb; and R = ArMes over the less-bent structures by 13–29 kJ·mol−1.
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6
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Wu H, Wu XN, Liu X, Ji C, Li W, Jiang L, Xie H, Zhou M. Iridium Dimer Anion-Mediated C≡C Triple Bond Cleavage and Successive Dehydrogenation of Acetylene in the Gas Phase. J Phys Chem A 2022; 126:1711-1717. [PMID: 35258303 DOI: 10.1021/acs.jpca.2c00664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reactions of the iridium dimer anion [Ir2]- with acetylene have been studied by mass spectrometry in the gas phase, which indicate that the [Ir2]- anion can consecutively react with C2H2 molecules to form the [Ir2C2x]- (x = 1, 2) and [Ir2C2yH2]- (y = 3-5) anions as major products with the successive release of H2 molecules at room temperature. The reactions are confirmed by the reactions of the mass-selected product [Ir2C2]- anion with C2H2 to produce [Ir2C4]- and [Ir2C2yH2]- (y = 3-5). Photoelectron spectra and quantum chemistry calculations confirm that the [Ir2C2x]- (x = 1, 2) product anions possess cyclic [Ir(μ-C)2Ir]- and [Ir(μ-C)(μ-C3)Ir]- structures, implying that the robust C≡C triple bond of acetylene can be completely cleaved by the [Ir2]- anion.
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Affiliation(s)
- Hechen Wu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
| | - Xiao-Nan Wu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
| | - Xuegang Liu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Chonglei Ji
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
| | - Wei Li
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
| | - Ling Jiang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Hua Xie
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Mingfei Zhou
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
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7
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Chen TY, Zheng Z, Zhang X, Chen J, Cha L, Tang Y, Guo Y, Zhou J, Wang B, Liu HW, Chang WC. Deciphering the Reaction Pathway of Mononuclear Iron Enzyme-Catalyzed N≡C Triple Bond Formation in Isocyanide Lipopeptide and Polyketide Biosynthesis. ACS Catal 2022; 12:2270-2279. [PMID: 35992736 PMCID: PMC9390461 DOI: 10.1021/acscatal.1c04869] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Despite the diversity of reactions catalyzed by 2-oxoglutarate-dependent nonheme iron (Fe/2OG) enzymes identified in recent years, only a limited number of these enzymes have been investigated in mechanistic detail. In particular, several Fe/2OG-dependent enzymes capable of catalyzing isocyanide formation have been reported. While the glycine moiety has been identified as a biosynthon for the isocyanide group, how the actual conversion is effected remains obscure. To elucidate the catalytic mechanism, we characterized two previously unidentified (AecA and AmcA) along with two known (ScoE and SfaA) Fe/2OG-dependent enzymes that catalyze N≡C triple bond installation using synthesized substrate analogues and potential intermediates. Our results indicate that isocyanide formation likely entails a two-step sequence involving an imine intermediate that undergoes decarboxylation-assisted desaturation to yield the isocyanide product. Results obtained from the in vitro experiments are further supported by mutagenesis, the product-bound enzyme structure, and in silico analysis.
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Affiliation(s)
| | | | | | - Jinfeng Chen
- State Key Laboratory of Bio-Organic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai 200032, China
| | - Lide Cha
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Yijie Tang
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Yisong Guo
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Jiahai Zhou
- State Key Laboratory of Bio-Organic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai 200032, China; CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Hung-wen Liu
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States; Division of Chemical Biology & Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Wei-chen Chang
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
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8
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Nguyen TL, Bross DH, Ruscic B, Ellison GB, Stanton J. Mechanism, Thermochemistry, and Kinetics of the Reversible Reactions: C2H3 + H2 ⇌ C2H4 + H ⇌ C2H5. Faraday Discuss 2022; 238:405-430. [DOI: 10.1039/d1fd00124h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High-level coupled cluster theory, in conjunction with Active Thermochemical Tables (ATcT) and E,J-resolved master equation calculations were used in a study of the title reactions, which play an important role...
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9
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Zhang L, Wei C, Wu J, Liu D, Yao Y, Chen Z, Liu J, Yao CJ, Li D, Yang R, Xia Z. Photoinduced inverse Sonogashira coupling reaction. Chem Sci 2022; 13:7475-7481. [PMID: 35872819 PMCID: PMC9241966 DOI: 10.1039/d2sc01933g] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/27/2022] [Indexed: 12/17/2022] Open
Abstract
A transition-metal and photocatalyst-free, photoinduced inverse Sonogashira coupling reaction was developed. Under visible-light irradiation, the excited state iodoalkyne acted as an “alkynyl radical synthetic equivalent”.
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Affiliation(s)
- Lizhu Zhang
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Cunbo Wei
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Jiawen Wu
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Dan Liu
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yinchao Yao
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Zhuo Chen
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Jianxun Liu
- School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Chang-Jiang Yao
- School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Dinghua Li
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Rongjie Yang
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Zhonghua Xia
- School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China
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10
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Zhou M, Wang HF. Insight into the photoexcitation effect on the catalytic activation of H2 and C-H bonds on TiO2(110) surface. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2021.12.074] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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Palmer C, Gordon MJ, Metiu H, McFarland EW. Influence of hydrocarbon feed additives on the high-temperature pyrolysis of methane in molten salt bubble column reactors. REACT CHEM ENG 2022. [DOI: 10.1039/d1re00517k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molten salts are excellent heat transfer fluids and a potential reaction environment for methane pyrolysis in which solid carbon can be continuously produced and separated from the liquid phase. Significant...
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12
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Conder CJ, Jawale H, Wenthold PG. Mass spectrometry studies of nitrene anions. MASS SPECTROMETRY REVIEWS 2021:e21751. [PMID: 34842299 DOI: 10.1002/mas.21751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 11/03/2021] [Indexed: 06/13/2023]
Abstract
Nitrene anions are a class of reactive intermediates that provide a means for studying the corresponding neutral molecules via electron photodetachment spectroscopy and photoelectron spectroscopy. The added electron makes it possible for protected nitrene anions to be manipulated by external electric and magnetic fields of a mass spectrometer. Nitrene anions also display their own unique reactivities as reagents, which have been investigated using ion/molecule reactions. Mass spectrometry of negative ions has thereby provided information on the electronic states, reactivities, and thermochemical properties of nitrene intermediates. This review also includes a discussion of condensed-phase nitrene anions.
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Affiliation(s)
- Cory J Conder
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
| | - Harshal Jawale
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
| | - Paul G Wenthold
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
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13
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Wilhelm C, Raiser D, Schubert H, Sindlinger CP, Wesemann L. Phosphine-Stabilized Germasilenylidene: Source for a Silicon-Atom Transfer. Inorg Chem 2021; 60:9268-9272. [PMID: 34165290 DOI: 10.1021/acs.inorgchem.1c01361] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A phosphine-stabilized germasilenylidene is synthesized following the pathway of SiCl4 oxidative addition at a germylene-phosphine Lewis pair. Low-temperature reduction using {(MesNacnac)Mg}2 resulted in a chlorosilylene intermediate and finally a molecule exhibiting a Ge═Si: motif. Inside the chelating phosphine-germylene, a low-valent silicon atom is stabilized and was transferred to diazabutadiene to give N-heterocyclic silylenes. Because of the high reactivity of the phosphine-stabilized germasilenylidene, a reaction of two Ge═Si: units was found to yield a Si2Ge2-ring molecule exhibiting a germasilene substituted with a silylene.
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Affiliation(s)
- Christian Wilhelm
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Dominik Raiser
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Hartmut Schubert
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Christian P Sindlinger
- Institut für Anorganische Chemie, Georg-August Universität Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany
| | - Lars Wesemann
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
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14
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Jaramillo-Botero A, Cable ML, Hofmann AE, Malaska M, Hodyss R, Lunine J. Understanding Hypervelocity Sampling of Biosignatures in Space Missions. ASTROBIOLOGY 2021; 21:421-442. [PMID: 33749334 PMCID: PMC7994429 DOI: 10.1089/ast.2020.2301] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 11/09/2020] [Indexed: 05/08/2023]
Abstract
The atomic-scale fragmentation processes involved in molecules undergoing hypervelocity impacts (HVIs; defined as >3 km/s) are challenging to investigate via experiments and still not well understood. This is particularly relevant for the consistency of biosignals from small-molecular-weight neutral organic molecules obtained during solar system robotic missions sampling atmospheres and plumes at hypervelocities. Experimental measurements to replicate HVI effects on neutral molecules are challenging, both in terms of accelerating uncharged species and isolating the multiple transition states over very rapid timescales (<1 ps). Nonequilibrium first-principles-based simulations extend the range of what is possible with experiments. We report on high-fidelity simulations of the fragmentation of small organic biosignature molecules over the range v = 1-12 km/s, and demonstrate that the fragmentation fraction is a sensitive function of velocity, impact angle, molecular structure, impact surface material, and the presence of surrounding ice shells. Furthermore, we generate interpretable fragmentation pathways and spectra for velocity values above the fragmentation thresholds and reveal how organic molecules encased in ice grains, as would likely be the case for those in "ocean worlds," are preserved at even higher velocities than bare molecules. Our results place ideal spacecraft encounter velocities between 3 and 5 km/s for bare amino and fatty acids and within 4-6 km/s for the same species encased in ice grains and predict the onset of organic fragmentation in ice grains at >5 km/s, both consistent with recent experiments exploring HVI effects using impact-induced ionization and analysis via mass spectrometry and from the analysis of Enceladus organics in Cassini Data. From nanometer-sized ice Ih clusters, we establish that HVI energy is dissipated by ice casings through thermal resistance to the impact shock wave and that an upper fragmentation velocity limit exists at which ultimately any organic contents will be cleaved by the surrounding ice-this provides a fundamental path to characterize micrometer-sized ice grains. Altogether, these results provide quantifiable insights to bracket future instrument design and mission parameters.
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Affiliation(s)
- Andres Jaramillo-Botero
- Chemistry and Chemical Engineering Division, California Institute of Technology, Pasadena, California, USA
| | - Morgan L. Cable
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Amy E. Hofmann
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Michael Malaska
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Robert Hodyss
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Jonathan Lunine
- Department of Astronomy and Carl Sagan Institute, Cornell University, Ithaca, New York, USA
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15
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Saá C, Varela JA, Álvarez-Pérez A. Oxidation of Alkynes via Catalytic Metal-Vinylidenes. SYNTHESIS-STUTTGART 2020. [DOI: 10.1055/s-0040-1707860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Metal-vinylidenes, generated by treatment of terminal alkynes with transition metals, are very useful intermediates in modern synthetic chemistry as shown by the high number of transformations in which they are involved. When a metal-vinylidene is generated in the presence of an oxidant, its immediate oxidation to a ketene occurs. In this short review, recent synthetic applications of the oxidation of alkynes via ketene intermediates from initially formed metal-vinylidenes are highlighted.1 Introduction2 Oxidation of Metal-Vinylidenes with Internal Oxidants3 Oxidation of Metal-Vinylidenes with External Oxidants4 Conclusions
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Affiliation(s)
- Carlos Saá
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela
| | - Jesús A. Varela
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela
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16
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Miyamoto K, Narita S, Masumoto Y, Hashishin T, Osawa T, Kimura M, Ochiai M, Uchiyama M. Room-temperature chemical synthesis of C 2. Nat Commun 2020; 11:2134. [PMID: 32358541 PMCID: PMC7195449 DOI: 10.1038/s41467-020-16025-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 04/02/2020] [Indexed: 11/09/2022] Open
Abstract
Diatomic carbon (C2) is historically an elusive chemical species. It has long been believed that the generation of C2 requires extremely high physical energy, such as an electric carbon arc or multiple photon excitation, and so it has been the general consensus that the inherent nature of C2 in the ground state is experimentally inaccessible. Here, we present the chemical synthesis of C2 from a hypervalent alkynyl-λ3-iodane in a flask at room temperature or below, providing experimental evidence to support theoretical predictions that C2 has a singlet biradical character with a quadruple bond, thus settling a long-standing controversy between experimental and theoretical chemists, and that C2 serves as a molecular element in the bottom-up chemical synthesis of nanocarbons such as graphite, carbon nanotubes, and C60. Diatomic carbon (C2) is historically an elusive chemical species, considered to require high physical energy for its generation. Here, the authors describe the first room-temperature chemical synthesis of C2 and present experimental evidence for its singlet biradical (quadruple bonding) character and role as a molecular element of nanocarbons.
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Affiliation(s)
- Kazunori Miyamoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
| | - Shodai Narita
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yui Masumoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Takahiro Hashishin
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Taisei Osawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Mutsumi Kimura
- Division of Chemistry and Materials, Faculty of Textile Science and Technology, Shinshu University, Ueda, 386-8567, Japan.,Research Initiative for Supra-Materials (RISM), Shinshu University, Ueda, 386-8567, Japan
| | - Masahito Ochiai
- Graduate School of Pharmaceutical Sciences, University of Tokushima, 1-78 Shomachi, Tokushima, 770-8505, Japan
| | - Masanobu Uchiyama
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. .,Research Initiative for Supra-Materials (RISM), Shinshu University, Ueda, 386-8567, Japan. .,Cluster of Pioneering Research (CPR), Advanced Elements Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan.
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17
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Abstract
The use of an acetylene (ethynyl) group in medicinal chemistry coincides with the launch of the Journal of Medicinal Chemistry in 1959. Since then, the acetylene group has been broadly exploited in drug discovery and development. As a result, it has become recognized as a privileged structural feature for targeting a wide range of therapeutic target proteins, including MAO, tyrosine kinases, BACE1, steroid receptors, mGlu5 receptors, FFA1/GPR40, and HIV-1 RT. Furthermore, a terminal alkyne functionality is frequently introduced in chemical biology probes as a click handle to identify molecular targets and to assess target engagement. This Perspective is divided into three parts encompassing: (1) the physicochemical properties of the ethynyl group, (2) the advantages and disadvantages of the ethynyl group in medicinal chemistry, and (3) the impact of the ethynyl group on chemical biology approaches.
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Affiliation(s)
- Tanaji T Talele
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, Queens, New York 11439, United States
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18
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Amati M, Stoia S, Baerends EJ. The Electron Affinity as the Highest Occupied Anion Orbital Energy with a Sufficiently Accurate Approximation of the Exact Kohn-Sham Potential. J Chem Theory Comput 2020; 16:443-452. [PMID: 31794657 PMCID: PMC6964414 DOI: 10.1021/acs.jctc.9b00981] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Negative ions are not accurately represented in density
functional
approximations (DFAs) such as (semi)local density functionals (LDA
or GGA or meta-GGA). This is caused by the much too high orbital energies
(not negative enough) with these DFAs compared to the exact Kohn–Sham
values. Negative ions very often have positive DFA HOMO energies,
hence they are unstable. These problems do not occur with the exact
Kohn–Sham potential, the anion HOMO energy then being equal
to minus the electron affinity. It is therefore desirable to develop
sufficiently accurate approximations to the exact Kohn–Sham
potential. There are further beneficial effects on the orbital shapes
and the density of using a good approximation to the exact KS potential.
Notably the unoccupied orbitals are not unduly diffuse, as they are
in the Hartree–Fock model, with hybrid functionals, and even
with (semi)local density functional approximations (LDFAs). We show
that the recently developed B-GLLB-VWN approximation [Gritsenko et
al. J. Chem. Phys.2016, 144, 204114] to the exact KS potential affords stable negative ions
with HOMO orbital energy close to minus the electron affinity.
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Affiliation(s)
- M Amati
- Università degli Studi della Basilicata , Viale dell'Ateneo Lucano 10 , 85100 Potenza , Italy
| | - S Stoia
- Università degli Studi della Basilicata , Viale dell'Ateneo Lucano 10 , 85100 Potenza , Italy
| | - E J Baerends
- Sectie Theoretische Chemie, FEW , Vrije Universiteit , De Boelelaan 1083 , 1081 HV Amsterdam , The Netherlands
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19
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Le Vaillant F, Waser J. Alkynylation of radicals: spotlight on the "Third Way" to transfer triple bonds. Chem Sci 2019; 10:8909-8923. [PMID: 31762975 PMCID: PMC6855197 DOI: 10.1039/c9sc03033f] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 08/12/2019] [Indexed: 12/20/2022] Open
Abstract
The alkynylation of radical intermediates has been known since a long time, but had not been broadly applied in synthetic chemistry, in contrast to the alkynylation of either electrophiles or nucleophiles. In the last decade however, it has been intensively investigated leading to new disconnections to introduce versatile triple bonds into organic compounds. Nowadays, such processes are important alternatives to classical nucleophilic and electrophilic alkynylations. Efficient alkyne transfer reagents, in particular arylsulfones and hypervalent iodine reagents were introduced. Direct alkynylation, as well as cascade reactions, were subsequently developed. If relatively harsh conditions were required in the past, a new era began with progress in photoredox and transition metal catalysis. Starting from various radical precursors, alkynylations under very mild reaction conditions were rapidly discovered. This review covers the evolution of radical alkynylation, from its emergence to its current intensive stage of development. It will focus in particular on improvements for the generation of radicals and on the extension of the scope of radical precursors and alkyne sources.
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Affiliation(s)
- Franck Le Vaillant
- Laboratory of Catalysis and Organic Synthesis , Ecole Polytechnique Fédérale de Lausanne , EPFL SB ISIC LCSO , BCH 4306 , 1015 Lausanne , Switzerland .
| | - Jérôme Waser
- Laboratory of Catalysis and Organic Synthesis , Ecole Polytechnique Fédérale de Lausanne , EPFL SB ISIC LCSO , BCH 4306 , 1015 Lausanne , Switzerland .
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20
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Tatosian I, Bubas A, Iacovino A, Kline S, Metzler L, Van Stipdonk M. Formation and hydrolysis of gas-phase [UO 2 (R)] + : R═CH 3 , CH 2 CH 3 , CH═CH 2 , and C 6 H 5. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:780-789. [PMID: 31426122 DOI: 10.1002/jms.4430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/05/2019] [Accepted: 08/12/2019] [Indexed: 06/10/2023]
Abstract
The goals of the present study were (a) to create positively charged organo-uranyl complexes with general formula [UO2 (R)]+ (eg, R═CH3 and CH2 CH3 ) by decarboxylation of [UO2 (O2 C─R)]+ precursors and (b) to identify the pathways by which the complexes, if formed, dissociate by collisional activation or otherwise react when exposed to gas-phase H2 O. Collision-induced dissociation (CID) of both [UO2 (O2 C─CH3 )]+ and [UO2 (O2 C─CH2 CH3 )]+ causes H+ transfer and elimination of a ketene to leave [UO2 (OH)]+ . However, CID of the alkoxides [UO2 (OCH2 CH3 )]+ and [UO2 (OCH2 CH2 CH3 )]+ produced [UO2 (CH3 )]+ and [UO2 (CH2 CH3 )]+ , respectively. Isolation of [UO2 (CH3 )]+ and [UO2 (CH2 CH3 )]+ for reaction with H2 O caused formation of [UO2 (H2 O)]+ by elimination of ·CH3 and ·CH2 CH3 : Hydrolysis was not observed. CID of the acrylate and benzoate versions of the complexes, [UO2 (O2 C─CH═CH2 )]+ and [UO2 (O2 C─C6 H5 )]+ , caused decarboxylation to leave [UO2 (CH═CH2 )]+ and [UO2 (C6 H5 )]+ , respectively. These organometallic species do react with H2 O to produce [UO2 (OH)]+ , and loss of the respective radicals to leave [UO2 (H2 O)]+ was not detected. Density functional theory calculations suggest that formation of [UO2 (OH)]+ , rather than the hydrated UV O2 + , cation is energetically favored regardless of the precursor ion. However, for the [UO2 (CH3 )]+ and [UO2 (CH2 CH3 )]+ precursors, the transition state energy for proton transfer to generate [UO2 (OH)]+ and the associated neutral alkanes is higher than the path involving direct elimination of the organic neutral to form [UO2 (H2 O)]+ . The situation is reversed for the [UO2 (CH═CH2 )]+ and [UO2 (C6 H5 )]+ precursors: The transition state for proton transfer is lower than the energy required for creation of [UO2 (H2 O)]+ by elimination of CH═CH2 or C6 H5 radical.
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Affiliation(s)
- Irena Tatosian
- Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Ave, Pittsburgh, Pennsylvania, 15282, USA
| | - Amanda Bubas
- Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Ave, Pittsburgh, Pennsylvania, 15282, USA
- Department of Chemistry, University of Utah, 215 1400 E, Salt Lake City, UT, 84112
| | - Anna Iacovino
- Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Ave, Pittsburgh, Pennsylvania, 15282, USA
| | - Susan Kline
- Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Ave, Pittsburgh, Pennsylvania, 15282, USA
| | - Luke Metzler
- Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Ave, Pittsburgh, Pennsylvania, 15282, USA
| | - Michael Van Stipdonk
- Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Ave, Pittsburgh, Pennsylvania, 15282, USA
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21
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Ortiz de Montellano PR. Acetylenes: cytochrome P450 oxidation and mechanism-based enzyme inactivation. Drug Metab Rev 2019; 51:162-177. [PMID: 31203694 DOI: 10.1080/03602532.2019.1632891] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The oxidation of carbon-carbon triple bonds by cytochrome P450 produces ketene metabolites that are hydrolyzed to acetic acid derivatives or are trapped by nucleophiles. In the special case of 17α-ethynyl sterols, D-ring expansion and de-ethynylation have been observed as competing pathways. The oxidation of acetylenic groups is also associated with mechanism-based inactivation of cytochrome P450 enzymes. One mechanism for this inactivation is reaction of the ketene metabolite with cytochrome P450 residues essential for substrate binding or catalysis. However, in the case of monosubstituted acetylenes, inactivation can also occur by addition of the oxidized acetylenic function to a nitrogen of the heme prosthetic group. This addition reaction is not mediated by the ketene metabolite, but rather occurs during oxygen transfer to the triple bond. In some instances, a detectable intermediate is formed that is most consistent with a ketocarbene-iron heme complex. This complex can progress to the N-alkylated heme or revert back to the unmodified enzyme. The ketocarbene complex may intervene in the formation of all the N-alkyl heme adducts, but is normally too unstable to be detected.
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22
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Sebbar N, Bozzelli JW, Trimis D, Bockhorn H. Thermochemistry and kinetics of the 2‐butanone‐4‐yl CH
3
C(=O)CH
2
CH
2
• + O
2
reaction system. INT J CHEM KINET 2019. [DOI: 10.1002/kin.21276] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- N. Sebbar
- KIT‐ Karlsruhe Institute of TechnologyEngler‐Bunte‐Institut Karlsruhe Germany
| | - J. W. Bozzelli
- Department of Chemical Engineering, Chemistry and Environmental ScienceNew Jersey Institute of Technology Newark, New Jersey
| | - D. Trimis
- KIT‐ Karlsruhe Institute of TechnologyEngler‐Bunte‐Institut Karlsruhe Germany
| | - H. Bockhorn
- KIT‐ Karlsruhe Institute of TechnologyEngler‐Bunte‐Institut Karlsruhe Germany
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23
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Harris T, Alabugin IV. Strain and stereoelectronics in cycloalkyne click chemistry. MENDELEEV COMMUNICATIONS 2019. [DOI: 10.1016/j.mencom.2019.05.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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24
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Hegemann D, Nisol B, Gaiser S, Watson S, Wertheimer MR. Energy conversion efficiency in low- and atmospheric-pressure plasma polymerization processes with hydrocarbons. Phys Chem Chem Phys 2019; 21:8698-8708. [PMID: 30989155 DOI: 10.1039/c9cp01567a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Since the earliest days of this field there has been an interest in correlating the structure of plasma polymer (PP) coatings with deposition parameters, most particularly with energy input per monomer molecule, Em. Both of our laboratories have developed methods for measuring Em (or somewhat equivalent, the apparent activation energy, Ea) in low- (LP) and atmospheric-pressure (AP) electrical discharge plasmas. We recently proposed a new parameter, energy conversion efficiency (ECE), which for the first time permits direct comparison of LP and AP experiments. Here, we report the case of small hydrocarbons, namely acetylene, ethylene and methane. "Critical" Em (or Ea) values that demarcate ECE regimes separating different reaction mechanisms are found to agree remarkably well, and to correlate with specific reaction mechanisms, including dissociation, recombination, gas-phase oligomerization, and surface processes.
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Affiliation(s)
- Dirk Hegemann
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Plasma & Coating Group, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland.
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25
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Lang W, Harold MP. Rate Inhibition and Enhancement on Ceria-Promoted Pd Monolith Catalysts: Oxidation of Acetylene, Ethylene, and Propylene and Their Mixtures. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b00978] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Wendy Lang
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204, United States
| | - Michael P. Harold
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204, United States
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26
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Krebs KM, Hanselmann D, Schubert H, Wurst K, Scheele M, Wesemann L. Phosphine-Stabilized Digermavinylidene. J Am Chem Soc 2019; 141:3424-3429. [DOI: 10.1021/jacs.8b13645] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Kilian M. Krebs
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Dominik Hanselmann
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Hartmut Schubert
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Kai Wurst
- Institut für Physikalische und Theoretische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Marcus Scheele
- Institut für Physikalische und Theoretische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Lars Wesemann
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
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27
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Liu Y, Lu N, Tang J. Synthesis, characterization, crystal structure, and antioxidant activity of hexahydro-β-acids. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2018.08.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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28
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Kumagai Y, Odagiri T, Nakano M, Suzuki IH, Hosaka K, Kitajima M, Kouchi N. Formation of hot hydrogen atoms from superexcited states of acetylene. J Chem Phys 2018; 149:244302. [PMID: 30599704 DOI: 10.1063/1.5058101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The cross sections for the formation of the H(2p) and H(2s) atoms, σ 2p and σ 2s , respectively, in photoexcitation of C2H2 were obtained in an absolute scale for studying formation and decay of superexcited states in the extreme ultraviolet range. Several superexcited states of C2H2 including multiply excited states were found in the curve of the σ 2p cross sections as a function of the incident photon energy. The same states seem to contribute to the variation in the σ 2s cross sections as well, which can be ascribed to the non-adiabatic transitions between the 2p and 2s channels. The Σ/Π symmetry-resolved cross sections for the H(2s) atom formation, σ 2 s Σ and σ 2 s Π , were also obtained on an absolute scale. The coupling between the Σ u + 1 and 1Π u states was found to be small.
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Affiliation(s)
- Yoshiaki Kumagai
- Department of Chemistry, Tokyo Institute of Technology, Tokyo 152-8551, Japan
| | - Takeshi Odagiri
- Department of Materials and Life Sciences, Sophia University, Tokyo 102-8554, Japan
| | - Motoyoshi Nakano
- Department of Chemistry, Tokyo Institute of Technology, Tokyo 152-8551, Japan
| | - Isao H Suzuki
- Department of Materials and Life Sciences, Sophia University, Tokyo 102-8554, Japan
| | - Kouichi Hosaka
- Department of Chemistry, Tokyo Institute of Technology, Tokyo 152-8551, Japan
| | - Masashi Kitajima
- Department of Chemistry, Tokyo Institute of Technology, Tokyo 152-8551, Japan
| | - Noriyuki Kouchi
- Department of Chemistry, Tokyo Institute of Technology, Tokyo 152-8551, Japan
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29
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Wang ED, Li GY, Ding JX, He GZ. Unexpected chemistry from the homogeneous thermal decomposition of acetylene: An ab initio study. CHINESE J CHEM PHYS 2018. [DOI: 10.1063/1674-0068/31/cjcp1802019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- En-dong Wang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Guang-yue Li
- College of Chemical Engineering, North China University of Science and Technology, Tangshan 063009, China
| | - Jun-xia Ding
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, China
| | - Guo-zhong He
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, China
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30
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Slanina Z, Uhlík F, Pan C, Akasaka T, Lu X, Adamowicz L. Computed stabilization for a giant fullerene endohedral: Y2C2@C1(1660)-C108. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2018.08.051] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Ghale SB, Lanorio JG, Nickel AA, Ervin KM. Conformational Effects on Gas-Phase Acidities of Isomeric C3 and C5 Alkanols. J Phys Chem A 2018; 122:7797-7807. [DOI: 10.1021/acs.jpca.8b06851] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Surja B. Ghale
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, MS 216, Reno, Nevada 89557-0216, United States
| | - Jerry G. Lanorio
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, MS 216, Reno, Nevada 89557-0216, United States
| | - Alex A. Nickel
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, MS 216, Reno, Nevada 89557-0216, United States
| | - Kent M. Ervin
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, MS 216, Reno, Nevada 89557-0216, United States
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32
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Shoshani MM, Johnson SA. Cooperative carbon-atom abstraction from alkenes in the core of a pentanuclear nickel cluster. Nat Chem 2017. [DOI: 10.1038/nchem.2840] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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33
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A stable heavier group 14 analogue of vinylidene. Nat Chem 2016; 8:1022-1026. [PMID: 27768110 DOI: 10.1038/nchem.2597] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 07/15/2016] [Indexed: 11/08/2022]
Abstract
Vinylidene (H2C=C) is a member of the family of compounds of composition CH (and isomeric with ethyne, HC≡CH), but it has been observed only transiently-with a lifetime in the region of 0.1 ns. Indeed, no simple (non-base-stabilized) compounds of the type R2E=E have been characterized structurally for any of the group 14 elements. Here we show that by employing the bulky and strongly electron-donating boryl ligand (HCDippN)2B (Dipp, 2,6-iPr2C6H3), a simple monomeric digermavinylidene compound, (boryl)2GeGe, can be synthesized and is stable at room temperature. Both its formation via the two-electron chemical oxidation of the symmetrical Ge0 compound K2[(boryl)GeGe(boryl)] and its subsequent reaction chemistry (for example, with H2), are consistent with a high substituent lability and the accessibility of both 1,1- and 1,2-substitution patterns. Structural and computational studies of [(HCDippN)2B]2GeGe reveal a weak Ge-Ge double bond-the π component of which contributes to the highest occupied molecular orbital (HOMO)-with a Ge-centred lone pair as the HOMO-1.
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34
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Mahamulkar S, Yin K, Davis RJ, Shibata H, Malek A, Jones CW, Agrawal PK. In Situ Generation of Radical Coke and the Role of Coke-Catalyst Contact on Coke Oxidation. Ind Eng Chem Res 2016. [DOI: 10.1021/acs.iecr.6b00556] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shilpa Mahamulkar
- School
of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Kehua Yin
- Department
of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Robert J. Davis
- Department
of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Hirokazu Shibata
- Hydrocarbons R&D, Dow Benelux, NL 4530 AA, Terneuzen, Netherlands
| | - Andrzej Malek
- Hydrocarbons R&D, The Dow Chemical Company, Midland, Michigan 48674, United States
| | - Christopher W. Jones
- School
of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Pradeep K. Agrawal
- School
of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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35
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Zeng T, Danovich D, Shaik S, Ananth N, Hoffmann R. Tuning the Ground State Symmetry of Acetylenyl Radicals. ACS CENTRAL SCIENCE 2015; 1:270-278. [PMID: 27162981 PMCID: PMC4827494 DOI: 10.1021/acscentsci.5b00187] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Indexed: 06/05/2023]
Abstract
The lowest excited state of the acetylenyl radical, HCC, is a (2)Π state, only 0.46 eV above the ground state, (2)Σ(+). The promotion of an electron from a π bond pair to a singly occupied σ hybrid orbital is all that is involved, and so we set out to tune those orbital energies, and with them the relative energetics of (2)Π and (2)Σ(+) states. A strategy of varying ligand electronegativity, employed in a previous study on substituted carbynes, RC, was useful, but proved more difficult to apply for substituted acetylenyl radicals, RCC. However, π-donor/acceptor substitution is effective in modifying the state energies. We are able to design molecules with (2)Π ground states (NaOCC, H2NCC ((2)A″), HCSi, FCSi, etc.) and vary the (2)Σ(+)-(2)Π energy gap over a 4 eV range. We find an inconsistency between bond order and bond dissociation energy measures of the bond strength in the Si-containing molecules; we provide an explanation through an analysis of the relevant potential energy curves.
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Affiliation(s)
- Tao Zeng
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
| | - David Danovich
- Institute
of Chemistry and The Lise Meitner-Minerva Center for Computational
Quantum Chemistry, Hebrew University of
Jerusalem, 91904 Jerusalem, Israel
| | - Sason Shaik
- Institute
of Chemistry and The Lise Meitner-Minerva Center for Computational
Quantum Chemistry, Hebrew University of
Jerusalem, 91904 Jerusalem, Israel
| | - Nandini Ananth
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
| | - Roald Hoffmann
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
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36
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Savee JD, Borkar S, Welz O, Sztáray B, Taatjes CA, Osborn DL. Multiplexed Photoionization Mass Spectrometry Investigation of the O(3P) + Propyne Reaction. J Phys Chem A 2015; 119:7388-403. [DOI: 10.1021/acs.jpca.5b00491] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- John D. Savee
- Combustion
Research Facility, Sandia National Laboratories, Mail Stop 9055, Livermore, California 94551-0969, United States
| | - Sampada Borkar
- Department
of Chemistry, University of the Pacific, Stockton, California 95211, United States
| | - Oliver Welz
- Combustion
Research Facility, Sandia National Laboratories, Mail Stop 9055, Livermore, California 94551-0969, United States
| | - Bálint Sztáray
- Department
of Chemistry, University of the Pacific, Stockton, California 95211, United States
| | - Craig A. Taatjes
- Combustion
Research Facility, Sandia National Laboratories, Mail Stop 9055, Livermore, California 94551-0969, United States
| | - David L. Osborn
- Combustion
Research Facility, Sandia National Laboratories, Mail Stop 9055, Livermore, California 94551-0969, United States
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37
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Ruscic B. Active Thermochemical Tables: Sequential Bond Dissociation Enthalpies of Methane, Ethane, and Methanol and the Related Thermochemistry. J Phys Chem A 2015; 119:7810-37. [PMID: 25760799 DOI: 10.1021/acs.jpca.5b01346] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Active Thermochemical Tables (ATcT) thermochemistry for the sequential bond dissociations of methane, ethane, and methanol systems were obtained by analyzing and solving a very large thermochemical network (TN). Values for all possible C-H, C-C, C-O, and O-H bond dissociation enthalpies at 298.15 K (BDE298) and bond dissociation energies at 0 K (D0) are presented. The corresponding ATcT standard gas-phase enthalpies of formation of the resulting CHn, n = 4-0 species (methane, methyl, methylene, methylidyne, and carbon atom), C2Hn, n = 6-0 species (ethane, ethyl, ethylene, ethylidene, vinyl, ethylidyne, acetylene, vinylidene, ethynyl, and ethynylene), and COHn, n = 4-0 species (methanol, hydroxymethyl, methoxy, formaldehyde, hydroxymethylene, formyl, isoformyl, and carbon monoxide) are also presented. The ATcT thermochemistry of carbon dioxide, water, hydroxyl, and carbon, oxygen, and hydrogen atoms is also included, together with the sequential BDEs of CO2 and H2O. The provenances of the ATcT enthalpies of formation, which are quite distributed and involve a large number of relevant determinations, are analyzed by variance decomposition and discussed in terms of principal contributions. The underlying reasons for periodic appearances of remarkably low and/or unusually high BDEs, alternating along the dissociation sequences, are analyzed and quantitatively rationalized. The present ATcT results are the most accurate thermochemical values currently available for these species.
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Affiliation(s)
- Branko Ruscic
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States.,Computation Institute, University of Chicago, Chicago, Illinois 60637, United States
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38
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Fu HR, Zhang J. Structural Transformation and Hysteretic Sorption of Light Hydrocarbons in a Flexible Zn-Pyrazole-Adenine Framework. Chemistry 2015; 21:5700-3. [DOI: 10.1002/chem.201406323] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Indexed: 11/09/2022]
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39
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Agafonov GL, Bilera IV, Vlasov PA, Kolbanovskii YA, Smirnov VN, Tereza AM. Soot formation during the pyrolysis and oxidation of acetylene and ethylene in shock waves. KINETICS AND CATALYSIS 2015. [DOI: 10.1134/s0023158415010012] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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40
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Cao Y, Zhao J, Zou X, Jin PP, Chen H, Gao R, Zhou LJ, Zou YC, Li GD. Synthesis of porous In2O3 microspheres as a sensitive material for early warning of hydrocarbon explosions. RSC Adv 2015. [DOI: 10.1039/c4ra13763a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We report the template-free synthesis of porous nanoparticle-assembled In2O3 microspheres that can serve as a highly sensitive material for the detection of C1–C3 hydrocarbons.
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Affiliation(s)
- Yang Cao
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- China
| | - Jun Zhao
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- China
| | - Xiaoxin Zou
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- China
| | - Pan-Pan Jin
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- China
| | - Hui Chen
- School of Materials Science and Engineering
- China University of Mining and Technology
- Xuzhou 221000
- China
| | - Ruiqin Gao
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- China
| | - Li-Jing Zhou
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- China
| | - Yong-Cun Zou
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- China
| | - Guo-Dong Li
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- China
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41
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Aresta M, Dibenedetto A, Baran T, Wojtyła S, Macyk W. Solar energy utilization in the direct photocarboxylation of 2,3-dihydrofuran using CO2. Faraday Discuss 2015; 183:413-27. [DOI: 10.1039/c5fd00040h] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The conversion of CO2 into high energy products (fuels) and the direct carboxylation of C–H bonds require a high energy input. Energy cannot be derived from fossil carbon, in this case. Solar energy can be used instead, with a low environmental impact and good profit. We have studied the use of white light or solar energy in the photoreduction of CO2 and in photocarboxylation reactions, using different semiconductors modified at their surface. Two examples of reduction of CO2 to methanol and CO will be shortly discussed, and two cases of carboxylation of organic substrates. The case of carboxylation of 2,3-dihydrofuran will be discussed in detail.
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Affiliation(s)
| | | | | | - Szymon Wojtyła
- Faculty of Chemistry
- Jagiellonian University in Kraków
- 30-060 Kraków
- Poland
| | - Wojciech Macyk
- Faculty of Chemistry
- Jagiellonian University in Kraków
- 30-060 Kraków
- Poland
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42
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McIntosh GJ, Russell DK. Experimental and theoretical studies into the formation of C4-C6 products in partially chlorinated hydrocarbon pyrolysis systems: a probabilistic approach to congener-specific yield predictions. J Phys Chem A 2014; 118:8644-63. [PMID: 25225996 DOI: 10.1021/jp5015516] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This work presents a study of the pyrolytic formation of vinylacetylene and benzene congeners formed from chlorinated hydrocarbon precursors, a complex, multipath polymerization system formed in a monomer-rich environment. (Co-)pyrolyses of dichloro- and trichloroethylene yield a rich array of products, and assuming a single dominant underlying growth mechanism, this (on comparing expected and observed products) allows a number of potentially competing channels to C4 and C6 products to be ruled out. Poor congener/isomer descriptions rule out even-carbon radical routes, and the absence of C3 and C5 products rule out odd-carbon processes. Vinylidenes appear unable to describe the increased reactivity of acetylenes with chlorination noted in our experiments, leaving molecular acetylene dimerization processes and, in C6 systems, the closely related Diels-Alder cyclization as the likely reaction mechanism. The feasibility of these routes is further supported by ab initio calculations. However, some of the most persuasive evidence is provided by congener-specific yield predictions enabled by the construction of a probability tree analogue of kinetic modeling. This approach is relatively quick to construct, provides surprisingly accurate predictions, and may be a very useful tool in screening for important reaction channels in poorly understood congener- or isomer-rich reaction systems.
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Affiliation(s)
- Grant J McIntosh
- School of Chemical Sciences, University of Auckland , Private Bag 92019, Auckland 1010, New Zealand
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43
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Khalilov U, Bogaerts A, Neyts EC. Microscopic mechanisms of vertical graphene and carbon nanotube cap nucleation from hydrocarbon growth precursors. NANOSCALE 2014; 6:9206-9214. [PMID: 24981176 DOI: 10.1039/c4nr00669k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Controlling and steering the growth of single walled carbon nanotubes is often believed to require controlling of the nucleation stage. Yet, little is known about the microscopic mechanisms governing the nucleation from hydrocarbon molecules. Specifically, we address here the dehydrogenation of hydrocarbon molecules and the formation of all-carbon graphitic islands on metallic nanoclusters from hydrocarbon molecules under conditions typical for carbon nanotube growth. Employing reactive molecular dynamics simulations, we demonstrate for the first time that the formation of a graphitic network occurs through the intermediate formation of vertically oriented, not fully dehydrogenated graphitic islands. Upon dehydrogenation of these vertical graphenes, the islands curve over the surface, thereby forming a carbon network covering the nanoparticle. The results indicate that controlling the extent of dehydrogenation offers an additional parameter to control the nucleation of carbon nanotubes.
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Affiliation(s)
- Umedjon Khalilov
- Department of Chemistry, Research Group PLASMANT, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium.
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44
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Danovich D, Hiberty PC, Wu W, Rzepa HS, Shaik S. The nature of the fourth bond in the ground state of C2: the quadruple bond conundrum. Chemistry 2014; 20:6220-32. [PMID: 24782210 DOI: 10.1002/chem.201400356] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Does, or doesn't C2 break the glass ceiling of triple bonding? This work provides an overview on the bonding conundrum in C2 and on the recent discussions regarding our proposal that it possesses a quadruple bond. As such, we focus herein on the main point of contention, the 4th bond of C2, and discuss the main views. We present new data and an overview of the nature of the 4th bond--its proposed antiferromagnetically coupled nature, its strength, and a derivation of its bond energy from experimentally based thermochemical data. We address the bond-order conundrum of C2 arising from generalized VB (GVB) calculations by comparing it to HC≡CH, and showing that the two molecules behave very similarly, and C2 is in no way an exception. We analyse the root cause of the deviation of C2 from the Badger Rule, and demonstrate that the reason for the smaller force constant (FC) of C2 relative to HC≡CH has nothing to do with the bond energies, or with the number of bonds in the two molecules. The FC is determined primarily by the bond length, which is set by the balance between the bond length preferences of the σ- versus π-bonds in the two molecules. This interplay in the case of C2 clearly shows the fingerprints of the 4th bond. Our discussion resolves the points of contention and shows that the arguments used to dismiss the quadruple bond nature of C2 are not well founded.
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Affiliation(s)
- David Danovich
- Institute of Chemistry and Lise Meitner Center for Computational Quantum Chemistry, The Hebrew University, Jerusalem 91904 (Israel), Fax: (+972) 2-6584680
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45
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Affiliation(s)
| | - Steven R. Kass
- Department
of Chemistry, University of Minnesota,
Minneapolis, Minnesota 55455,
United States
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46
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Lee H, Baraban JH, Field RW, Stanton JF. High-Accuracy Estimates for the Vinylidene-Acetylene Isomerization Energy and the Ground State Rotational Constants of :C═CH2. J Phys Chem A 2013; 117:11679-83. [DOI: 10.1021/jp400035a] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hyunwoo Lee
- Department of Chemistry and
Biochemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Joshua H. Baraban
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts
02139, United States
| | - Robert W. Field
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts
02139, United States
| | - John F. Stanton
- Department of Chemistry and
Biochemistry, University of Texas at Austin, Austin, Texas 78712, United States
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47
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Affiliation(s)
- W. Carl Lineberger
- JILA and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309;
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48
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Liang JX, Wang YB, Geng ZY, Wang YZ, Wang YC. Gas-phase reaction of the isobutenyl anion with N2O from ab initio calculations. J STRUCT CHEM+ 2013. [DOI: 10.1134/s0022476613020030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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49
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Lin Y, Wang H, Gao S, Li R, Schaefer HF. Hydrogen-Bonded Double-Proton Transfer in Five Guanine–Cytosine Base Pairs after Hydrogen Atom Addition. J Phys Chem B 2012; 116:8908-15. [DOI: 10.1021/jp3048746] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuexia Lin
- School of
Physical Science and
Technology, Southwest Jiaotong University, Chengdu 610031, P. R. China
| | - Hongyan Wang
- School of
Physical Science and
Technology, Southwest Jiaotong University, Chengdu 610031, P. R. China
| | - Simin Gao
- School of
Physical Science and
Technology, Southwest Jiaotong University, Chengdu 610031, P. R. China
| | - Ruhu Li
- School of
Physical Science and
Technology, Southwest Jiaotong University, Chengdu 610031, P. R. China
| | - Henry F. Schaefer
- Center for Computational Quantum
Chemistry, University of Georgia, Athens,
Georgia 30602, United States
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50
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Tabor DP, Harding ME, Ichino T, Stanton JF. High-Accuracy Extrapolated Ab Initio Thermochemistry of the Vinyl, Allyl, and Vinoxy Radicals. J Phys Chem A 2012; 116:7668-76. [DOI: 10.1021/jp302527n] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Daniel P. Tabor
- Institute for Theoretical Chemistry, Department of
Chemistry and Biochemistry, The University of Texas at Austin, 105 E. 24th St., A5300, Austin, Texas 78712-0165,
United States
| | - Michael E. Harding
- Institute for Theoretical Chemistry, Department of
Chemistry and Biochemistry, The University of Texas at Austin, 105 E. 24th St., A5300, Austin, Texas 78712-0165,
United States
| | - Takatoshi Ichino
- Institute for Theoretical Chemistry, Department of
Chemistry and Biochemistry, The University of Texas at Austin, 105 E. 24th St., A5300, Austin, Texas 78712-0165,
United States
| | - John F. Stanton
- Institute for Theoretical Chemistry, Department of
Chemistry and Biochemistry, The University of Texas at Austin, 105 E. 24th St., A5300, Austin, Texas 78712-0165,
United States
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