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Shao C, Wang Q, Zhang W, Bennett A, Li Y, Guo J, Im HG, Roberts WL, Violi A, Sarathy SM. Elucidating the polycyclic aromatic hydrocarbons involved in soot inception. Commun Chem 2023; 6:223. [PMID: 37845500 PMCID: PMC10579345 DOI: 10.1038/s42004-023-01017-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 09/29/2023] [Indexed: 10/18/2023] Open
Abstract
Polycyclic aromatic hydrocarbons are the main precursors to soot particles in combustion systems. A lack of direct experimental evidence has led to controversial theoretical explanations for the transition from gas-phase species to organic soot clusters. This work focuses on sampling infant soot particles from well-defined flames followed by analysis using state-of-the-art mass spectrometry. We found that PAH molecules present in soot particles are all stabilomers. Kinetic Monte Carlo simulations and thermodynamic stability calculations further identify the detected PAHs as peri-condensed and without aliphatic chains. Van der Waals forces can easily link PAHs of such size and shape to form PAH dimers and larger clusters under the specified flame conditions. Our results provide direct experimental evidence that soot inception is initiated by a physical process under typical flame conditions. This work improves our understanding of aerosol particulates, which has implications for their environmental and climate change impacts.
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Affiliation(s)
- Can Shao
- King Abdullah University of Science and Technology (KAUST), Clean Combustion Research Center, Thuwal, 23955-6900, Saudi Arabia.
| | - Qi Wang
- Department of Mechanical Engineering, University of Michigan, 2350 Hayward St, Ann Arbor, MI, 48109-2125, USA
| | - Wen Zhang
- King Abdullah University of Science and Technology (KAUST), Core Labs, Thuwal, 23955-6900, Saudi Arabia.
| | - Anthony Bennett
- King Abdullah University of Science and Technology (KAUST), Clean Combustion Research Center, Thuwal, 23955-6900, Saudi Arabia
| | - Yang Li
- King Abdullah University of Science and Technology (KAUST), Clean Combustion Research Center, Thuwal, 23955-6900, Saudi Arabia
- Science and Technology on Combustion, Internal Flow and Thermostructure Laboratory, School of Astronautics, Northwestern Polytechnical University, 710072, Xi'an, China
| | - Junjun Guo
- King Abdullah University of Science and Technology (KAUST), Clean Combustion Research Center, Thuwal, 23955-6900, Saudi Arabia
| | - Hong G Im
- King Abdullah University of Science and Technology (KAUST), Clean Combustion Research Center, Thuwal, 23955-6900, Saudi Arabia
| | - William L Roberts
- King Abdullah University of Science and Technology (KAUST), Clean Combustion Research Center, Thuwal, 23955-6900, Saudi Arabia
| | - Angela Violi
- Department of Mechanical Engineering, University of Michigan, 2350 Hayward St, Ann Arbor, MI, 48109-2125, USA
- Department of Chemical Engineering, University of Michigan, 2350 Hayward St, Ann Arbor, MI, 48109-2125, USA
- Chemical Engineering and Biophysics Program, University of Michigan, 930 N. University Ave, Ann Arbor, MI, 48109-1055, USA
| | - S Mani Sarathy
- King Abdullah University of Science and Technology (KAUST), Clean Combustion Research Center, Thuwal, 23955-6900, Saudi Arabia.
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2
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Zhu X, Chen Z, Ai H. Mechanistic insight into the tautomerization of histidine initiated by water-catalyzed N-H and C-H cleavages. J Mol Model 2022; 28:325. [PMID: 36136156 DOI: 10.1007/s00894-022-05222-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 07/12/2022] [Indexed: 10/14/2022]
Abstract
The N-H and C-H activation is of great significance in organic chemistry and chemical industry fields, especially, in the utilization of petroleum raw materials. High NδH (tautomer of natural histidine) content would increase Alzheimer's disease risk. To inhibit this and improve the activation of N-H and C-H bonds, the isomerization mechanism from NδH to NεH of histidine-containing dipeptide catalyzed by water cluster was explored. The results discovered that water cluster assists this reaction by reducing the activation energies from 68.20 to 9.60 kcal mol-1, and its size not only affects the reaction rate but also determines the reaction pathway in a degree. Moreover, water cluster, taken as a potential green catalyst, is more effective on the reactions involving N-H and C-H bond cleavages than reported common toxic organometallic compounds and has different catalytic mechanisms. This work also provides some theoretical guidance for the modulation of Alzheimer's disease induced by histidine isomerization.
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Affiliation(s)
- Xueying Zhu
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, People's Republic of China.
| | - Zijiao Chen
- Institute of Science and Technology, Xinjiang University, Aksu, 843100, People's Republic of China
| | - Hongqi Ai
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, People's Republic of China.
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3
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Mirzaei MS, Taherpour AA, Wentrup C. Azulene-Naphthalene, Naphthalene-Naphthalene, and Azulene-Azulene Rearrangements. J Org Chem 2022; 87:11503-11518. [PMID: 35960863 DOI: 10.1021/acs.joc.2c01099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mechanism(s) of thermal rearrangement of azulenes have been enigmatic for several decades. Herein, we have employed density functional theory (DFT) calculations at the M06-2X/6-311+G(d,p) level together with single-point calculations at the CCSD(T) level to assess possible mechanisms of the experimentally observed azulene and naphthalene automerizations. Of the two mechanisms proposed for naphthalene automerization, it is found that the benzofulvene (BF) route is favored over the naphthvalene mechanism by ∼6 kcal/mol and is energetically lower than the norcaradiene-vinylidene mechanism (NVM) for the azulene-naphthalene rearrangement (Ea ∼ 76.5 (74.6) kcal/mol). Moreover, contrary to older reports, we observe that a pathway involving indenylcarbene intermediates is a viable, alternate mechanism. Therefore, the naphthalene automerization is expected to take place during azulene pyrolysis, especially under conditions of low-pressure FVP, where it will be aided by chemical activation. Furthermore, thermal azulene-azulene isomerization is feasible through vinylidene-acetylene-vinylidene (VAV), dehydrotriquinacene (DTQ), and azulvalene (AV) pathways with activation energies lying below that required for the azulene-naphthalene conversion, i.e., the NVM. These results, together with the previously published NVM, provide reasonable explanations for most of the products of the thermal azulene-naphthalene rearrangement.
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Affiliation(s)
- M Saeed Mirzaei
- Department of Chemistry, University of Pittsburgh, 219 Parkman Ave., Pittsburgh, Pennsylvania 15260, United States
| | - Avat Arman Taherpour
- Flinders Centre for NanoScale Science and Technology, Flinders University, Adelaide, South Australia 5001, Australia
| | - Curt Wentrup
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland 4072, Australia
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4
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Mirzaei MS, Taherpour AA, Wentrup C. Thermal Rearrangement of Azulenes to Naphthalenes: A Deeper Insight into the Mechanisms. J Org Chem 2022; 87:3296-3310. [PMID: 35157471 DOI: 10.1021/acs.joc.1c02948] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The thermal rearrangement of azulene to naphthalene has been the subject of several experimental and computational studies. Here, we reexamine the proposed mechanisms at the DFT level. The use of different functionals showed that the HF-exchange contribution significantly affects reaction energies and barrier heights. Accordingly, all proposed pathways were investigated with the optimal method, M06-2X/6-311+G(d,p), which confirms the norcaradiene-vinylidene mechanism (A) as the dominant unimolecular route (Ea ≈ 76 kcal/mol) able to account for the major products of pyrolyses using 13C- or substituent-labeled azulenes. Moreover, a facile vinylidene-acetylene interconversion will scramble the terminal carbon atoms in the vinylidene. Several other potential intramolecular reaction mechanisms (B-E) are ruled out because of higher activation energies (>84 kcal/mol) and failure to reproduce the results obtained with substituted and 13C-labeled azulenes and benzazulenes. These experimental results also demonstrate that the proposed free radical or H atom-induced intermolecular methylene walk and spiran mechanisms cannot be major contributors, especially under flash vacuum pyrolysis conditions.
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Affiliation(s)
- M Saeed Mirzaei
- Department of Organic Chemistry, Faculty of Chemistry, Razi University, Kermanshah 67149-67346, Iran
| | - Avat Arman Taherpour
- Department of Organic Chemistry, Faculty of Chemistry, Razi University, Kermanshah 67149-67346, Iran
| | - Curt Wentrup
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland 4072, Australia
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5
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Guo QH, Qiu Y, Wang MX, Fraser Stoddart J. Aromatic hydrocarbon belts. Nat Chem 2021; 13:402-419. [DOI: 10.1038/s41557-021-00671-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 02/23/2021] [Indexed: 01/22/2023]
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6
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Chen P, Fatayer S, Schuler B, Metz JN, Gross L, Yao N, Zhang Y. The Role of Methyl Groups in the Early Stage of Thermal Polymerization of Polycyclic Aromatic Hydrocarbons Revealed by Molecular Imaging. ENERGY & FUELS : AN AMERICAN CHEMICAL SOCIETY JOURNAL 2021; 35:2224-2233. [PMID: 33574639 PMCID: PMC7869141 DOI: 10.1021/acs.energyfuels.0c04016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/23/2020] [Indexed: 05/03/2023]
Abstract
The initial thermal reactions of aromatic hydrocarbons are relevant to many industrial applications. However, tracking the growing number of heavy polycyclic aromatic hydrocarbon (PAH) products is extremely challenging because many reactions are unfolding in parallel from a mixture of molecules. Herein, we studied the reactions of 2,7-dimethylpyrene (DMPY) to decipher the roles of methyl substituents during mild thermal treatment. We found that the presence of methyl substituents is key for reducing the thermal severity required to initiate chemical reactions in natural molecular mixtures. A complex mixture of thermal products including monomers, dimers, and trimers was characterized by NMR, mass spectrometry, and noncontact atomic force microscopy (nc-AFM). A wide range of structural transformations including methyl transfer and polymerization reactions were identified. A detailed mechanistic understanding on the roles of H radicals during the polymerization of polycyclic aromatic hydrocarbons was obtained.
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Affiliation(s)
- Pengcheng Chen
- Princeton
Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey 08540, United States
| | - Shadi Fatayer
- IBM
Research−Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - Bruno Schuler
- Empa,
Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Jordan N. Metz
- Corporate
Strategic Research, ExxonMobil Research
and Engineering Company, 1545 Route 22 E., Annandale, New Jersey 08801, United States
| | - Leo Gross
- IBM
Research−Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - Nan Yao
- Princeton
Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey 08540, United States
| | - Yunlong Zhang
- Corporate
Strategic Research, ExxonMobil Research
and Engineering Company, 1545 Route 22 E., Annandale, New Jersey 08801, United States
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7
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The thermal rearrangements of naphthalene and azulene. An analysis through the bent bond and antiperiplanar hypothesis orbital model. Tetrahedron 2021. [DOI: 10.1016/j.tet.2021.131956] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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8
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Zlatković D, Dallinger D, Kappe CO. A novel pathway for the thermolysis of N-nitrosoanthranilates using flash vacuum pyrolysis leading to 7-aminophthalides. Org Biomol Chem 2020; 18:8371-8375. [PMID: 33063810 DOI: 10.1039/d0ob01946a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Flash vacuum pyrolysis of methyl N-methyl-N-nitrosoanthranilate leads to elimination of nitric oxide and disproportionation of the formed N-radical to 7-(methylamino)phthalide and methyl N-methylanthranilate. This transformation was found to be a convenient, solvent-free method for the preparation of 7-(methylamino)phthalides. An alternative route through pyrolysis of N-benzyl-N-methyl anthranilates was also investigated.
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Affiliation(s)
- Dragan Zlatković
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria. and Department of Chemistry, Faculty of Sciences and Mathematics, University of Niš, Višegradska 33, 18000 Niš, Serbia
| | - Doris Dallinger
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria. and Center for Continuous Flow Synthesis and Processing (CCFLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
| | - C Oliver Kappe
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstrasse 28, 8010 Graz, Austria. and Center for Continuous Flow Synthesis and Processing (CCFLOW), Research Center Pharmaceutical Engineering GmbH (RCPE), Inffeldgasse 13, 8010 Graz, Austria
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9
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Lungerich D, Hitzenberger JF, Ruppel M, Döpper T, Witt M, Ivanović-Burmazović I, Görling A, Jux N, Drewello T. Gas-Phase Transformation of Fluorinated Benzoporphyrins to Porphyrin-Embedded Conical Nanocarbons. Chemistry 2020; 26:12180-12187. [PMID: 32578918 PMCID: PMC7540561 DOI: 10.1002/chem.202002638] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Indexed: 01/07/2023]
Abstract
Geodesic nitrogen-containing graphene fragments are interesting candidates for various material applications, but the available synthetic protocols, which need to overcome intrinsic strain energy during the formation of the bowl-shaped skeletons, are often incompatible with heteroatom-embedded structures. Through this mass spectrometry-based gas-phase study, we show by means of collision-induced dissociation experiments and supported by density functional theory calculations, the first evidence for the formation of a porphyrin-embedded conical nanocarbon. The influences of metalation and functionalization of the used tetrabenzoporphyrins have been investigated, which revealed different cyclization efficiencies, different ionization possibilities, and a variation of the dissociation pathway. Our results suggest a stepwise process for HF elimination from the fjord region, which supports a selective pathway towards bent nitrogen-containing graphene fragments.
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Affiliation(s)
- Dominik Lungerich
- Department of Chemistry and Pharmacy, & Interdisciplinary Center for Molecular Materials (ICMM), Organic Chemistry II, Friedrich-Alexander-University Erlangen-Nuernberg, Nikolaus-Fiebiger-Str. 10, 91058, Erlangen, Germany.,Center for Nanomedicine, Institute for Basic Science (IBS), Seoul, 03722, Republic of Korea.,Graduate Program of Nano Biomedical Engineering (NanoBME), Advanced Science Institute, Yonsei University, Seoul, 03722, Republic of Korea
| | - Jakob Felix Hitzenberger
- Department of Chemistry and Pharmacy, Physical Chemistry I, Friedrich-Alexander-University Erlangen-Nuernberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Michael Ruppel
- Department of Chemistry and Pharmacy, & Interdisciplinary Center for Molecular Materials (ICMM), Organic Chemistry II, Friedrich-Alexander-University Erlangen-Nuernberg, Nikolaus-Fiebiger-Str. 10, 91058, Erlangen, Germany
| | - Tibor Döpper
- Department of Chemistry and Pharmacy, Theoretical Chemistry, Friedrich-Alexander-University Erlangen-Nuernberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Matthias Witt
- Bruker Daltonics GmbH, Fahrenheitstrasse 4, 28359, Bremen, Germany
| | - Ivana Ivanović-Burmazović
- Department of Chemistry and Pharmacy, Bioinorganic Chemistry, Friedrich-Alexander-University Erlangen-Nuernberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Andreas Görling
- Department of Chemistry and Pharmacy, Theoretical Chemistry, Friedrich-Alexander-University Erlangen-Nuernberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Norbert Jux
- Department of Chemistry and Pharmacy, & Interdisciplinary Center for Molecular Materials (ICMM), Organic Chemistry II, Friedrich-Alexander-University Erlangen-Nuernberg, Nikolaus-Fiebiger-Str. 10, 91058, Erlangen, Germany
| | - Thomas Drewello
- Department of Chemistry and Pharmacy, Physical Chemistry I, Friedrich-Alexander-University Erlangen-Nuernberg, Egerlandstrasse 3, 91058, Erlangen, Germany
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10
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Zyryanov GV, Kopchuk DS, Kovalev IS, Santra S, Rahman M, Khasanov AF, Krinochkin AP, Taniya OS, Chupakhin ON, Charushin VN. Rational synthetic methods in creating promising (hetero)aromatic molecules and materials. MENDELEEV COMMUNICATIONS 2020. [DOI: 10.1016/j.mencom.2020.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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11
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Deslongchamps G, Deslongchamps P. Bent Bond/Antiperiplanar Hypothesis and the Chemical Reactivity of Annulenes. J Org Chem 2020; 85:8645-8655. [PMID: 32501012 DOI: 10.1021/acs.joc.0c01069] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The properties and stereochemical reactivity of cyclobutadiene, benzene, cyclooctatetraene, and the [10]- to [14]annulenes can be uniformly rationalized through the bent bond/antiperiplanar hypothesis (BBAH). This new orbital model considers electronic delocalization between pyramidal diradical resonance structures and associated bent bonds, as it applies to aromatic, nonaromatic, and antiaromatic molecules.
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Affiliation(s)
- Ghislain Deslongchamps
- Department of Chemistry, University of New Brunswick, P.O. Box 4400, Fredericton, New Brunswick E3B 5A3, Canada
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12
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Suresh JR, Whitener G, Theumer G, Bröcher DJ, Bauer I, Massa W, Knölker H. Synthesis and Crystal Structure of Dimorphic Dibenzo[cde,opq]rubicene. Chemistry 2019; 25:13759-13765. [PMID: 31339614 PMCID: PMC6899531 DOI: 10.1002/chem.201902915] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Indexed: 11/09/2022]
Abstract
Dibenzo[cde,opq]rubicene has been synthesized by an eight-step reaction sequence including an iron-mediated [2+2+1] cycloaddition and a flash vacuum pyrolysis as key steps. Two crystal modifications of the S-shaped, planar polycyclic aromatic hydrocarbon have been obtained and characterized by X-ray diffractometry.
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Affiliation(s)
- Joghee R. Suresh
- Fakultät ChemieTechnische Universität DresdenBergstrasse 6601069DresdenGermany
| | - Glenn Whitener
- Fakultät ChemieTechnische Universität DresdenBergstrasse 6601069DresdenGermany
| | - Gabriele Theumer
- Fakultät ChemieTechnische Universität DresdenBergstrasse 6601069DresdenGermany
| | - Dirk J. Bröcher
- Fakultät ChemieTechnische Universität DresdenBergstrasse 6601069DresdenGermany
| | - Ingmar Bauer
- Fakultät ChemieTechnische Universität DresdenBergstrasse 6601069DresdenGermany
| | - Werner Massa
- Fachbereich ChemiePhilipps-Universität MarburgHans-Meerwein-Strasse 435043MarburgGermany
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13
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Parent JF, Deslongchamps P. High-Temperature Isomerization of Benzenoid Polycyclic Aromatic Hydrocarbons. Analysis through the Bent Bond and Antiperiplanar Hypothesis Orbital Model. J Org Chem 2018; 83:3299-3304. [PMID: 29470083 DOI: 10.1021/acs.joc.8b00095] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
L. T. Scott has discovered the 1,2-swapping of carbon and hydrogen atoms which is known to take place on benzenoid aromatics (up to ∼1000 °C range). For example, 13C-1-naphthalene is specifically converted to 13C-2-naphthalene, and there is evidence that this occurs through the formation of benzofulvene and a naphthalene-carbene intermediate. Application of the bent bond/antiperiplanar hypothesis leads to the postulate that higher in energy pyramidal singlet diradical intermediates can be used to propose a mechanism that rationalizes various atom rearrangements on benzenoid aromatics and related isomeric compounds.
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Affiliation(s)
- Jean-François Parent
- Département de Chimie, Faculté des Sciences et de Génie , 1045 avenue de la médecine , Université Laval , Québec , QC G1 V 0A6 , Canada
| | - Pierre Deslongchamps
- Département de Chimie, Faculté des Sciences et de Génie , 1045 avenue de la médecine , Université Laval , Québec , QC G1 V 0A6 , Canada
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14
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Affiliation(s)
- Curt Wentrup
- School of Chemistry and Molecular Biosciences The University of Queensland Brisbane Qld 4072 Australien
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15
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Wentrup C. Flash Vacuum Pyrolysis: Techniques and Reactions. Angew Chem Int Ed Engl 2017; 56:14808-14835. [PMID: 28675675 DOI: 10.1002/anie.201705118] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Indexed: 12/13/2022]
Abstract
Flash vacuum pyrolysis (FVP) had its beginnings in the 1940s and 1950s, mainly through mass spectrometric detection of pyrolytically formed free radicals. In the 1960s many organic chemists started performing FVP experiments with the purpose of isolating new and interesting compounds and understanding pyrolysis processes. Meanwhile, many different types of apparatus and techniques have been developed, and it is the purpose of this review to present the most important methods as well as a survey of typical reactions and observations that can be achieved with the various techniques. This includes preparative FVP, chemical trapping reactions, matrix isolation, and low temperature spectroscopy of reactive intermediates and unstable molecules, the use of online mass, photoelectron, microwave, and millimeterwave spectroscopies, gas-phase laser pyrolysis, pulsed pyrolysis with supersonic jet expansion, very low pressure pyrolysis for kinetic investigations, solution-spray and falling-solid FVP for involatile compounds, and pyrolysis over solid supports and reagents. Moreover, the combination of FVP with matrix isolation and photochemistry is a powerful tool for investigations of reaction mechanism.
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Affiliation(s)
- Curt Wentrup
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Qld, 4072, Australia
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16
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Affiliation(s)
- Curt Wentrup
- School of Chemistry and Molecular
Biosciences, The University of Queensland, Brisbane, Queensland 4072, Australia
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17
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Abstract
The first azacorannulene with a nitrogen on the rim, has been synthesized in seven steps from 4-bromoisoquinoline.
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Affiliation(s)
| | - A. K. Greene
- Merkert Chemistry Center
- Boston College
- Chestnut Hill
- USA
| | - L. T. Scott
- Merkert Chemistry Center
- Boston College
- Chestnut Hill
- USA
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