1
|
Vo TH, Korlacki R, Sinitskii A. Cis- trans isomerization of dimethyl 2,3-dibromofumarate. RSC Adv 2022; 12:32471-32474. [PMID: 36425717 PMCID: PMC9661881 DOI: 10.1039/d2ra05996g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 11/01/2022] [Indexed: 09/08/2024] Open
Abstract
The isomerization of dimethyl 2,3-dibromofumarate in chloroform solutions was investigated by the combination of nuclear magnetic resonance (NMR) and density functional theory (DFT) calculations. The bromination of dimethyl acetylenedicarboxylate leading to dimethyl 2,3-dibromofumarate produces the trans isomer initially, which however converts into the more stable cis isomer. The conversion from trans to cis is spontaneous and greatly accelerated by light.
Collapse
Affiliation(s)
- Timothy H Vo
- Department of Chemistry, University of Nebraska-Lincoln Lincoln 68588 NE USA
| | - Rafał Korlacki
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln Lincoln 68588 NE USA
| | - Alexander Sinitskii
- Department of Chemistry, University of Nebraska-Lincoln Lincoln 68588 NE USA
| |
Collapse
|
2
|
Peng Y, Yu W, Feng X, Xu T, Früchtl H, van Mourik T, Kirk SR, Jenkins S. The Cis-Effect Explained Using Next-Generation QTAIM. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27186099. [PMID: 36144830 PMCID: PMC9506152 DOI: 10.3390/molecules27186099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 09/05/2022] [Accepted: 09/14/2022] [Indexed: 11/22/2022]
Abstract
We used next-generation QTAIM (NG-QTAIM) to explain the cis-effect for two families of molecules: C2X2 (X = H, F, Cl) and N2X2 (X = H, F, Cl). We explained why the cis-effect is the exception rather than the rule. This was undertaken by tracking the motion of the bond critical point (BCP) of the stress tensor trajectories Tσ(s) used to sample the Uσ-space cis- and trans-characteristics. The Tσ(s) were constructed by subjecting the C1-C2 BCP and N1-N2 BCP to torsions ± θ and summing all possible Tσ(s) from the bonding environment. During this process, care was taken to fully account for multi-reference effects. We associated bond-bending and bond-twisting components of the Tσ(s) with cis- and trans-characteristics, respectively, based on the relative ease of motion of the electronic charge density ρ(rb). Qualitative agreement is found with existing experimental data and predictions are made where experimental data is not available.
Collapse
Affiliation(s)
- Yuting Peng
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China
| | - Wenjing Yu
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China
| | - Xinxin Feng
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China
| | - Tianlv Xu
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China
| | - Herbert Früchtl
- EaStCHEM School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, Scotland, UK
| | - Tanja van Mourik
- EaStCHEM School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, Scotland, UK
| | - Steven R. Kirk
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China
- Correspondence: (S.R.K.); (S.J.)
| | - Samantha Jenkins
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China
- Correspondence: (S.R.K.); (S.J.)
| |
Collapse
|
3
|
Datta S, Limpanuparb T. Steric effects vs. electron delocalization: a new look into the stability of diastereomers, conformers and constitutional isomers. RSC Adv 2021; 11:20691-20700. [PMID: 35479364 PMCID: PMC9033979 DOI: 10.1039/d1ra02877d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 05/24/2021] [Indexed: 01/22/2023] Open
Abstract
A quantum chemical investigation of the stability of compounds with identical formulas was carried out on 23 classes of compounds made of C, N, P, O and S atoms as core structures and halogens H, F, Cl, Br and I as substituents. All possible structures were generated and investigated by quantum mechanical methods. The prevalence of a formula in which its Z configuration, gauche conformation or meta isomer is the most stable form is calculated and discussed. Quantitative and qualitative models to explain the stability of the 23 classes of halogenated compounds were also proposed.
Collapse
Affiliation(s)
- Sopanant Datta
- Science Division, Mahidol University International College, Mahidol University Salaya Nakhon Pathom 73170 Thailand
| | - Taweetham Limpanuparb
- Science Division, Mahidol University International College, Mahidol University Salaya Nakhon Pathom 73170 Thailand
| |
Collapse
|
4
|
Uchimaru T, Mizukado J. Computational studies of fluorinated propenes: The fluorine "cis effect," barrier heights of the internal rotation of CX3 (X = H or F) group, and π-bond strengths. J Fluor Chem 2021. [DOI: 10.1016/j.jfluchem.2021.109772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
5
|
Singh SK, Panwaria P, Mishra KK, Das A. Steric as well as n→π* Interaction Controls the Conformational Preferences of Phenyl Acetate: Gas‐phase Spectroscopy and Quantum Chemical Calculations. Chem Asian J 2019; 14:4705-4711. [DOI: 10.1002/asia.201901158] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 09/03/2019] [Indexed: 01/26/2023]
Affiliation(s)
- Santosh K. Singh
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
- Current Address: Department of ChemistryUniversity of Hawaii, Manoa Honolulu Hawaii 96822 USA
| | - Prakash Panwaria
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
| | - Kamal K. Mishra
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
| | - Aloke Das
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
| |
Collapse
|
6
|
Tokuhashi K, Uchimaru T, Takizawa K, Kondo S. Rate Constants for the Reactions of OH Radicals with the ( E)/( Z) Isomers of CFCl=CFCl and ( E)-CHF=CHF. J Phys Chem A 2019; 123:4834-4843. [PMID: 31117589 DOI: 10.1021/acs.jpca.9b02454] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The rate constants for the OH radical reactions with halogenated ethenes were investigated experimentally and computationally. The rate constants for the reactions of OH radicals with ( E)-CFCl=CFCl ( k1), ( Z)-CFCl=CFCl ( k2), and ( E)-CHF=CHF ( k3) were measured using flash and laser photolysis methods. The temporal profile of the OH radical was monitored by a laser-induced fluorescence technique. Kinetic measurements were carried out over the temperature range of 250-430 K. Arrhenius rate constants were determined to be k1 = (1.67 ± 0.06) × 10-12·exp[(140 ± 10) K/ T], k2 = (1.75 ± 0.04) × 10-12·exp[(140 ± 10) K/ T], and k3 = (3.99 ± 0.15) × 10-12·exp[(260 ± 10) K/ T] cm3 molecule-1 s-1. The quoted uncertainties are 95% confidence levels and do not include systematic errors. Infrared absorption spectra were measured at room temperature. The atmospheric lifetimes and the global warming potentials of ( E)-CFCl=CFCl, ( Z)-CFCl=CFCl, and ( E)-CHF=CHF were estimated to be 4.3, 4.2, and 1.2 days and 0.035, 0.036, and 0.0056, respectively. The ozone depletion potentials of ( E)-CFCl=CFCl and ( Z)-CFCl=CFCl were determined to be 0.00011 and 0.00010, respectively. The photochemical ozone creation potentials of the halogenated ethenes were less than 1/4 that of ethene. In addition, the ( E)/( Z) differences in the energy and IR spectra of the CFCl=CFCl and CHF=CHF molecules were computationally examined. The reactivities of these halogenated ethenes toward OH radicals were investigated through the combination of DFT and ab initio computations. The rate constants calculated for the OH radical reactions of these halogenated ethenes showed reasonable agreement with the experimentally determined values. Our computational results for the CFCl=CFCl and CHF=CHF ( E)/( Z) isomeric pairs indicated that the rate constants toward OH radicals are larger for the higher-energy geometrical isomers than for the lower-energy counterparts.
Collapse
Affiliation(s)
- Kazuaki Tokuhashi
- National Institute of Advanced Industrial Science and Technology (AIST) , 1-1-1 Higashi , Tsukuba Ibaraki 305-8565 , Japan
| | - Tadafumi Uchimaru
- National Institute of Advanced Industrial Science and Technology (AIST) , 1-1-1 Higashi , Tsukuba Ibaraki 305-8565 , Japan
| | - Kenji Takizawa
- National Institute of Advanced Industrial Science and Technology (AIST) , 1-1-1 Higashi , Tsukuba Ibaraki 305-8565 , Japan
| | - Shigeo Kondo
- National Institute of Advanced Industrial Science and Technology (AIST) , 1-1-1 Higashi , Tsukuba Ibaraki 305-8565 , Japan
| |
Collapse
|
7
|
Alabugin IV, dos Passos Gomes G, Abdo MA. Hyperconjugation. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2018. [DOI: 10.1002/wcms.1389] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
8
|
Tavanaei L, Nori-Shargh D. New Insights into the Origin of the cis-Configuration Preferences in 1,2-Dihaloethenes: The Importance of the Bonding Orbital Deviations. Aust J Chem 2018. [DOI: 10.1071/ch17219] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The origin of the preferences for the cis-configurations in 1,2-difluoroethene (1), 1,2-dichloroethene (2), and 1,2-dibromoethene (3) were explored by means of the G3MP2, LC-ωPBE and CCSD(T) methods with the 6–311+G** basis set on all atoms, and natural bond orbital interpretation. On the basis of the results obtained, the cis-configurations preferences decrease in going from compound 1 to compound 3. Effectively, the deletions of the hyperconjugative interactions from the Fock matrices of the cis- and trans-configurations of compound 1 lead to the increase of the trans-conformation stability (by ~6.11 kcal mol−1) compared with its corresponding cis-conformation. However, the Pauli exchange-type repulsion difference between the cis- and trans-configurations of compound 1 is in favour of the trans-configuration (by ~6.25 kcal mol−1), revealing that the stabilization energies associated with the hyperconjugative interactions do not compensate the destabilizations associated with the exchange component and dipole-dipole interactions. Importantly, the C=C bond paths in the cis-configuration of compound 1 are bent in essentially the same direction (towards the C–F bonds), leading to an increased overlap and a stronger C–C bond, whereas the C–C bond paths in the trans-configuration are bent in opposite directions. Accordingly, the co-operative stabilizations associated with the bending of the C=C bond paths (towards the C–F bonds) and total hyperconjugative generalized anomeric effect overcome the destabilizations associated with the exchange component and dipole–dipole interactions, leading to the preference of the cis-configuration in compound 1. The deletions of all the donor–acceptor electronic interactions from the Fock matrices of the cis- and trans-configurations of compounds 2 and 3 lead to the increase of the trans-conformation stabilities compared with their corresponding cis-conformations, revealing the determining impacts of the hyperconjugative interactions on the configurational preferences in compounds 2 and 3.
Collapse
|
9
|
Uchimaru T, Tsuzuki S, Chen L, Mizukado J. Computational investigation of π-bond strengths in fluorinated ethylenes. J Fluor Chem 2017. [DOI: 10.1016/j.jfluchem.2016.12.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
10
|
Hejazi SA, Osman OI, Alyoubi AO, Aziz SG, Hilal RH. The Thermodynamic and Kinetic Properties of 2-Hydroxypyridine/2-Pyridone Tautomerization: A Theoretical and Computational Revisit. Int J Mol Sci 2016; 17:E1893. [PMID: 27854244 PMCID: PMC5133892 DOI: 10.3390/ijms17111893] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 10/30/2016] [Accepted: 10/31/2016] [Indexed: 01/01/2023] Open
Abstract
The gas-phase thermal tautomerization reaction between 2-hydroxypyridine (2-HPY) and 2-pyridone (2-PY) was investigated by applying 6-311++G** and aug-cc-pvdz basis sets incorporated into some density functional theory (DFT) and coupled cluster with singles and doubles (CCSD) methods. The geometrical structures, dipole moments, HOMO-LUMO energy gaps, total hyperpolarizability, kinetics and thermodynamics functions were monitored against the effects of the corrections imposed on these functionals. The small experimental energy difference between the two tautomers of 3.23 kJ/mol; was a real test of the accuracy of the applied levels of theory. M062X and CCSD methods predicted the preference of 2-HPY over 2-PY by 5-9 kJ/mol; while B3LYP functional favoured 2-PY by 1-3 kJ/mol. The CAM-B3LYP and ωB97XD functionals yielded mixed results depending on the basis set used. The source of preference of 2-HPY is the minimal steric hindrance and electrostatic repulsion that subdued the huge hyperconjugation in 2-PY. A 1,3-proton shift intramolecular gas-phase tautomerization yielded a high average activation of 137.152 kJ/mol; while the intermolecular mixed dimer interconversion gave an average barrier height of 30.844 kJ/mol. These findings are boosted by a natural bond orbital (NBO) technique. The low total hyperpolarizabilities of both tautomers mark out their poor nonlinear optical (NLO) behaviour. The enhancement of the total hyperpolarizability of 2-HPY over that of 2-PY is interpreted by the bond length alternation.
Collapse
Affiliation(s)
- Safiyah A Hejazi
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
| | - Osman I Osman
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
- Chemistry Department, Faculty of Science, University of Khartoum, P.O. Box 321, Khartoum 11111, Sudan.
| | - Abdulrahman O Alyoubi
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
| | - Saadullah G Aziz
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
| | - Rifaat H Hilal
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
- Chemistry Department, Faculty of Science, Cairo University, Cairo 11258, Egypt.
| |
Collapse
|
11
|
Mukaiyama T, Uchimaru T, Hayashi Y. The DFT Calculation with NBO Analysis of E/ Z Enamines Derived from α-Alkoxyaldehyde with Pyrrolidine. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2016. [DOI: 10.1246/bcsj.20150382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
| | - Tadafumi Uchimaru
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Yujiro Hayashi
- Department of Chemistry, Graduate School of Science, Tohoku University
| |
Collapse
|
12
|
Juaristi E, Notario R. Theoretical Evidence for the Relevance of n(F) → σ*(C–X) (X = H, C, O, S) Stereoelectronic Interactions. J Org Chem 2016; 81:1192-7. [DOI: 10.1021/acs.joc.5b02718] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eusebio Juaristi
- Departamento
de Química, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Apartado Postal 14-740, 07000 México, D. F. Mexico
| | - Rafael Notario
- Instituto
de Química Física Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| |
Collapse
|
13
|
Aziz SG, Osman OI, Elroby SA, Hilal RH. Gas-Phase Thermal Tautomerization of Imidazole-Acetic Acid: Theoretical and Computational Investigations. Int J Mol Sci 2015; 16:26347-62. [PMID: 26556336 PMCID: PMC4661818 DOI: 10.3390/ijms161125959] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 10/10/2015] [Accepted: 10/22/2015] [Indexed: 11/21/2022] Open
Abstract
The gas-phase thermal tautomerization reaction between imidazole-4-acetic (I) and imidazole-5-acetic (II) acids was monitored using the traditional hybrid functional (B3LYP) and the long-range corrected functionals (CAM-B3LYP and ωB97XD) with 6-311++G** and aug-cc-pvdz basis sets. The roles of the long-range and dispersion corrections on their geometrical parameters, thermodynamic functions, kinetics, dipole moments, Highest Occupied Molecular Orbital-Lowest Unoccupied Molecular Orbital (HOMO-LUMO) energy gaps and total hyperpolarizability were investigated. All tested levels of theory predicted the preference of I over II by 0.750-0.877 kcal/mol. The origin of predilection of I is assigned to the H-bonding interaction (nN8→σ*O14-H15). This interaction stabilized I by 15.07 kcal/mol. The gas-phase interconversion between the two tautomers assumed a 1,2-proton shift mechanism, with two transition states (TS), TS1 and TS2, having energy barriers of 47.67-49.92 and 49.55-52.69 kcal/mol, respectively, and an sp³-type intermediate. A water-assisted 1,3-proton shift route brought the barrier height down to less than 20 kcal/mol in gas-phase and less than 12 kcal/mol in solution. The relatively high values of total hyperpolarizability of I compared to II were interpreted and discussed.
Collapse
Affiliation(s)
- Saadullah G Aziz
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
| | - Osman I Osman
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
- Chemistry Department, Faculty of Science, University of Khartoum, P.O. Box 321, Khartoum 11111, Sudan.
| | - Shaaban A Elroby
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
- Chemistry Department, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt.
| | - Rifaat H Hilal
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
- Chemistry Department, Faculty of Science, Cairo University, Giza 12613, Egypt.
| |
Collapse
|
14
|
Kaiser EW, Pierce DS. Study of the Thermodynamics (Thermal and Cl Catalyzed) and Kinetics of the Cis and Trans Isomerizations of CF3CF═CHF, CF3CH═CHCF3, and CH3CH═CHCH3 in 100–950 Torr of N2 Diluent at 296–875 K: Effect of F and CF3 Substitution on the Isomerization Process Including the Fluorine “Cis Effect”. J Phys Chem A 2015. [DOI: 10.1021/acs.jpca.5b06265] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- E. W. Kaiser
- Department of Natural Sciences, University of Michigan—Dearborn, 4901 Evergreen Road, Dearborn, Michigan 48128, United States
| | - David S. Pierce
- Department of Natural Sciences, University of Michigan—Dearborn, 4901 Evergreen Road, Dearborn, Michigan 48128, United States
| |
Collapse
|
15
|
Okamoto N, Sueda T, Minami H, Miwa Y, Yanada R. Regioselective Iodoazidation of Alkynes: Synthesis of α,α-Diazidoketones. Org Lett 2015; 17:1336-9. [DOI: 10.1021/acs.orglett.5b00395] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Noriko Okamoto
- Faculty of Pharmaceutical
Sciences, Hiroshima International University, 5-1-1 Hirokoshingai, Kure, Hiroshima 737-0112, Japan
| | - Takuya Sueda
- Faculty of Pharmaceutical
Sciences, Hiroshima International University, 5-1-1 Hirokoshingai, Kure, Hiroshima 737-0112, Japan
| | - Hideki Minami
- Faculty of Pharmaceutical
Sciences, Hiroshima International University, 5-1-1 Hirokoshingai, Kure, Hiroshima 737-0112, Japan
| | - Yoshihisa Miwa
- Faculty of Pharmaceutical
Sciences, Hiroshima International University, 5-1-1 Hirokoshingai, Kure, Hiroshima 737-0112, Japan
| | - Reiko Yanada
- Faculty of Pharmaceutical
Sciences, Hiroshima International University, 5-1-1 Hirokoshingai, Kure, Hiroshima 737-0112, Japan
| |
Collapse
|
16
|
Osman OI. Experimental and Theoretical Investigation of the Pyrolysis Products of Iminodiacetonitrile, (N≡CCH2)2NH. J Phys Chem A 2014; 118:10934-43. [DOI: 10.1021/jp507397x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Osman I. Osman
- Chemistry Department, Faculty
of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia
- Chemistry Department, Faculty
of Science, University of Khartoum, P.O. Box
321, Khartoum 11111, Sudan
- School of Chemistry and Molecular
Sciences, University of Sussex, Brighton BN1 9QJ, United Kingdom
| |
Collapse
|
17
|
Demaison J, Császár AG, Groner P, Rudolph HD, Craig NC. Semiexperimental Equilibrium Structures for cis, cis- and trans, trans-1,4-Difluorobutadiene by the Mixed Estimation Method and Definitive Relative Energies of the Isomers. J Phys Chem A 2013; 117:13166-75. [DOI: 10.1021/jp4098183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Jean Demaison
- Laboratoire
de Physique des Lasers, Atomes et Molécules, Université de Lille 1, 59655 Villeneuve d’Ascq Cedex, France
| | - Attila G. Császár
- Laboratory of Molecular Structure and Dynamics,
Institute of Chemistry, Eötvös University, Pázmány
Péter sétány 1/A, H-1117 Budapest, Hungary
- MTA-ELTE
Research Group on Complex Chemical Systems, P.O. Box
32, H-1518 Budapest, Hungary
| | - Peter Groner
- Department of Chemistry, University of Missouri—Kansas City, Kansas City, Missouri 64110-2499, United States
| | | | - Norman C. Craig
- Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, United States
| |
Collapse
|
18
|
Osman OI, Elroby SAK, Hilal RH, Aziz SG. Theoretical characterization of gas-phase thermolysis products of ethane-1,2-diol, 2-chloroethanol and 2-fluoroethanol. Mol Phys 2013. [DOI: 10.1080/00268976.2012.739716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
19
|
Jenkins S, Kirk SR, Rong C, Yin D. The cis-effect using the topology of the electronic charge density. Mol Phys 2012. [DOI: 10.1080/00268976.2012.745631] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Samantha Jenkins
- a Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) and Key Laboratory of Resource Fine-Processing and Advanced Materials of Hunan Province , College of Chemistry and Chemical Engineering, Hunan Normal University , Changsha Hunan 410081 , China
| | - Steven R. Kirk
- a Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) and Key Laboratory of Resource Fine-Processing and Advanced Materials of Hunan Province , College of Chemistry and Chemical Engineering, Hunan Normal University , Changsha Hunan 410081 , China
| | - Chunying Rong
- a Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) and Key Laboratory of Resource Fine-Processing and Advanced Materials of Hunan Province , College of Chemistry and Chemical Engineering, Hunan Normal University , Changsha Hunan 410081 , China
| | - Dulin Yin
- a Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) and Key Laboratory of Resource Fine-Processing and Advanced Materials of Hunan Province , College of Chemistry and Chemical Engineering, Hunan Normal University , Changsha Hunan 410081 , China
| |
Collapse
|
20
|
Abstract
The MP2 and DFT/B3LYP methods at 6-311++G(d,p) and aug-cc-pdz basis sets have been used to probe the origin of relative stability preference for eclipsed acetaldehyde over its bisected counterpart. A relative energy stability range of 1.02 to 1.20 kcal/mol, in favor of the eclipsed conformer, was found and discussed. An NBO study at these chemistry levels complemented these findings and assigned the eclipsed acetaldehyde preference mainly to the vicinal antiperiplanar hyperconjugative interactions. The tautomeric interconversion between the more stable eclipsed acetaldehyde and vinyl alcohol has been achieved through a four-membered ring transition state (TS). The obtained barrier heights and relative stabilities of eclipsed acetaldehyde and the two conformers of vinyl alchol at these model chemistries have been estimated and discussed.
Collapse
|
21
|
Alabugin IV, Gilmore KM, Peterson PW. Hyperconjugation. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2011. [DOI: 10.1002/wcms.6] [Citation(s) in RCA: 214] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Igor V. Alabugin
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Kerry M. Gilmore
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Paul W. Peterson
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| |
Collapse
|
22
|
Feller D, Craig NC, Groner P, McKean DC. Ab Initio Coupled Cluster Determination of the Equilibrium Structures of cis- and trans-1,2-Difluoroethylene and 1,1-Difluoroethylene. J Phys Chem A 2010; 115:94-8. [DOI: 10.1021/jp109584k] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- David Feller
- Department of Chemistry, Washington State University, Pullman, Washington 99164-4630, United States, Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, United States, Department of Chemistry, University of Missouri—Kansas City, Missouri 64110-2499, United States, and School of Chemistry, University of Edinburgh, Edinburgh EH9 3JJ, United Kingdom
| | - Norman C. Craig
- Department of Chemistry, Washington State University, Pullman, Washington 99164-4630, United States, Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, United States, Department of Chemistry, University of Missouri—Kansas City, Missouri 64110-2499, United States, and School of Chemistry, University of Edinburgh, Edinburgh EH9 3JJ, United Kingdom
| | - Peter Groner
- Department of Chemistry, Washington State University, Pullman, Washington 99164-4630, United States, Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, United States, Department of Chemistry, University of Missouri—Kansas City, Missouri 64110-2499, United States, and School of Chemistry, University of Edinburgh, Edinburgh EH9 3JJ, United Kingdom
| | - Donald C. McKean
- Department of Chemistry, Washington State University, Pullman, Washington 99164-4630, United States, Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, United States, Department of Chemistry, University of Missouri—Kansas City, Missouri 64110-2499, United States, and School of Chemistry, University of Edinburgh, Edinburgh EH9 3JJ, United Kingdom
| |
Collapse
|
23
|
Abstract
The geometries of 19 different partially fluorinated butatrienes and their related butenyne isomers have been calculated at the Møller-Plesset second order perturbation theory level with Dunning's valence triple-zeta basis set. Final energies were determined at the CCSD(T)/cc-pVQZ level of theory. Increasing fluorine substitution has only a limited effect on the bond lengths but a substantial effect on the angles. The CCC bond angles of 4 of the 5 partially fluorinated butatrienes show a deviation of more than 2 degrees from collinearity, therefore representing angle-strained butatrienes. Increasing degree of fluorination has a substantial effect on the isomerization energies. The energy difference between the least stable enyne nonfluorinated at the acetylenic center and the most stable enyne fluorinated at the acetylenic center decreases from 66.8 kJ/mol, in case of the monofluorinated system, to 29.7 kJ/mol in the triple fluorinated system. The acetylenic F substitution is crucial in raising the energies of fluorinated but-1-en-3-yne relative to their butatriene isomers. Within the triple fluorinated system and unprecedented for all discussed molecules, 1,1,4-trifluoro-but-1-en-3-yne represents the only molecule fluorinated at the acetylenic center that is more stable than its triene isomer.
Collapse
Affiliation(s)
- Christian Ehm
- Institut für Chemie und Biochemie, Abt. Anorganische Chemie, Freie Universität Berlin, 14195 Berlin, Germany
| | | |
Collapse
|
24
|
Affiliation(s)
- Satoshi Inagaki
- Dapartment of Chemistry, Faculty of Engineering, Gifu University, Yanagido, Gifu, 501-1193, Japan,
| |
Collapse
|