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Classification of So-Called Non-Covalent Interactions Based on VSEPR Model. Molecules 2021; 26:molecules26164939. [PMID: 34443526 PMCID: PMC8399763 DOI: 10.3390/molecules26164939] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 08/06/2021] [Accepted: 08/12/2021] [Indexed: 11/20/2022] Open
Abstract
The variety of interactions have been analyzed in numerous studies. They are often compared with the hydrogen bond that is crucial in numerous chemical and biological processes. One can mention such interactions as the halogen bond, pnicogen bond, and others that may be classified as σ-hole bonds. However, not only σ-holes may act as Lewis acid centers. Numerous species are characterized by the occurrence of π-holes, which also may play a role of the electron acceptor. The situation is complicated since numerous interactions, such as the pnicogen bond or the chalcogen bond, for example, may be classified as a σ-hole bond or π-hole bond; it ultimately depends on the configuration at the Lewis acid centre. The disadvantage of classifications of interactions is also connected with their names, derived from the names of groups such as halogen and tetrel bonds or from single elements such as hydrogen and carbon bonds. The chaos is aggravated by the properties of elements. For example, a hydrogen atom can act as the Lewis acid or as the Lewis base site if it is positively or negatively charged, respectively. Hence names of the corresponding interactions occur in literature, namely hydrogen bonds and hydride bonds. There are other numerous disadvantages connected with classifications and names of interactions; these are discussed in this study. Several studies show that the majority of interactions are ruled by the same mechanisms related to the electron charge shifts, and that the occurrence of numerous interactions leads to specific changes in geometries of interacting species. These changes follow the rules of the valence-shell electron-pair repulsion model (VSEPR). That is why the simple classification of interactions based on VSEPR is proposed here. This classification is still open since numerous processes and interactions not discussed in this study may be included within it.
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Golub IE, Filippov OA, Belkova NV, Epstein LM, Shubina ES. The Reaction of Hydrogen Halides with Tetrahydroborate Anion and Hexahydro- closo-hexaborate Dianion. Molecules 2021; 26:molecules26123754. [PMID: 34202981 PMCID: PMC8235096 DOI: 10.3390/molecules26123754] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/13/2021] [Accepted: 06/15/2021] [Indexed: 11/16/2022] Open
Abstract
The mechanism of the consecutive halogenation of the tetrahydroborate anion [BH4]− by hydrogen halides (HX, X = F, Cl, Br) and hexahydro-closo-hexaborate dianion [B6H6]2− by HCl via electrophile-induced nucleophilic substitution (EINS) was established by ab initio DFT calculations [M06/6-311++G(d,p) and wB97XD/6-311++G(d,p)] in acetonitrile (MeCN), taking into account non-specific solvent effects (SMD model). Successive substitution of H− by X− resulted in increased electron deficiency of borohydrides and changes in the character of boron atoms from nucleophilic to highly electrophilic. This, in turn, increased the tendency of the B–H bond to transfer a proton rather than a hydride ion. Thus, the regularities established suggested that it should be possible to carry out halogenation more selectively with the targeted synthesis of halogen derivatives with a low degree of substitution, by stabilization of H2 complex, or by carrying out a nucleophilic substitution of B–H bonds activated by interaction with Lewis acids (BL3).
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Grabowski SJ. Hydrogen Bond and Other Lewis Acid-Lewis Base Interactions as Preliminary Stages of Chemical Reactions. Molecules 2020; 25:E4668. [PMID: 33066201 PMCID: PMC7587390 DOI: 10.3390/molecules25204668] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/09/2020] [Accepted: 10/10/2020] [Indexed: 01/21/2023] Open
Abstract
Various Lewis acid-Lewis base interactions are discussed as initiating chemical reactions and processes. For example, the hydrogen bond is often a preliminary stage of the proton transfer process or the tetrel and pnicogen bonds lead sometimes to the SN2 reactions. There are numerous characteristics of interactions being first stages of reactions; one can observe a meaningful electron charge transfer from the Lewis base unit to the Lewis acid; such interactions possess at least partly covalent character, one can mention other features. The results of different methods and approaches that are applied in numerous studies to describe the character of interactions are presented here. These are, for example, the results of the Quantum Theory of Atoms in Molecules, of the decomposition of the energy of interaction or of the structure-correlation method.
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Affiliation(s)
- Sławomir J. Grabowski
- Polimero eta Material Aurreratuak: Fisika, Kimika eta Teknologia, Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU & Donostia International Physics Center (DIPC) PK 1072, 20080 Donostia, Euskadi, Spain; ; Tel.: +34-943-018-187
- IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
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Belkova NV, Epstein LM, Filippov OA, Shubina ES. Hydrogen and Dihydrogen Bonds in the Reactions of Metal Hydrides. Chem Rev 2016; 116:8545-87. [PMID: 27285818 DOI: 10.1021/acs.chemrev.6b00091] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The dihydrogen bond-an interaction between a transition-metal or main-group hydride (M-H) and a protic hydrogen moiety (H-X)-is arguably the most intriguing type of hydrogen bond. It was discovered in the mid-1990s and has been intensively explored since then. Herein, we collate up-to-date experimental and computational studies of the structural, energetic, and spectroscopic parameters and natures of dihydrogen-bonded complexes of the form M-H···H-X, as such species are now known for a wide variety of hydrido compounds. Being a weak interaction, dihydrogen bonding entails the lengthening of the participating bonds as well as their polarization (repolarization) as a result of electron density redistribution. Thus, the formation of a dihydrogen bond allows for the activation of both the MH and XH bonds in one step, facilitating proton transfer and preparing these bonds for further transformations. The implications of dihydrogen bonding in different stoichiometric and catalytic reactions, such as hydrogen exchange, alcoholysis and aminolysis, hydrogen evolution, hydrogenation, and dehydrogenation, are discussed.
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Affiliation(s)
- Natalia V Belkova
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences , Vavilov Street 28, 119991 Moscow, Russia
| | - Lina M Epstein
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences , Vavilov Street 28, 119991 Moscow, Russia
| | - Oleg A Filippov
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences , Vavilov Street 28, 119991 Moscow, Russia
| | - Elena S Shubina
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences , Vavilov Street 28, 119991 Moscow, Russia
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5
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Ishikawa H, Kawasaki T, Inomata R. Infrared Spectroscopy of Phenol−Triethylsilane Dihydrogen-Bonded Cluster and its Cationic Analogues: Intrinsic Strength of the Si–H···H–O Dihydrogen Bond. J Phys Chem A 2015; 119:601-9. [DOI: 10.1021/jp5097508] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Haruki Ishikawa
- Department of Chemistry, School of Science, Kitasato University, Minami-ku, Sagamihara 252-0373, Japan
| | - Takayuki Kawasaki
- Department of Chemistry, School of Science, Kitasato University, Minami-ku, Sagamihara 252-0373, Japan
| | - Risa Inomata
- Department of Chemistry, School of Science, Kitasato University, Minami-ku, Sagamihara 252-0373, Japan
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Marincean S, Fritz M, Scamp R, Jackson JE. Mechanistic investigations in α-hydroxycarbonyls reduction by BH4-. J PHYS ORG CHEM 2013. [DOI: 10.1002/poc.2986] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Simona Marincean
- Department of Natural Sciences; University of Michigan- Dearborn; 4901 Evergreen Rd.; Dearborn; MI; 48128
| | | | - Ryan Scamp
- Department of Natural Sciences; University of Michigan- Dearborn; 4901 Evergreen Rd.; Dearborn; MI; 48128
| | - James E. Jackson
- Department of Chemistry; Michigan State University; East Lansing; MI; 48824
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Filippov OA, Belkova NV, Epstein LM, Lledos A, Shubina ES. Hydrogen–deuterium exchange in hydride chemistry: Dihydrogen bonded complexes as key intermediates. COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2012.07.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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9
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Marincean S, Jackson JE. Can hydridic-to-protonic hydrogen bonds catalyze hydride transfers in biological systems? J Phys Chem A 2010; 114:13376-80. [PMID: 21141894 DOI: 10.1021/jp1050854] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Catalysis of hydride transfer by hydridic-to-protonic hydrogen (HHH) bonding in α-hydroxy carbonyl isomerization reactions was examined computationally in the lithium salts of 7-substituted endo-3-hydroxybicyclo[2.2.1]hept-5-en-2-ones. The barrier for intramolecular hydride transfer in the parent system was calculated to be 17.2 kcal/mol. Traditional proton donors, such as OH and NH(3)(+), stabilized the metal cation-bridged transition state by 1.4 and 3.3 kcal/mol, respectively. Moreover, among the conformers of the OH systems, the one in which the proton donor is able to interact with the migrating hydride (H(m)) has an activation barrier lower by 1.3 and 1.7 kcal/mol than the other possible OH conformers. By contrast, the presence of an electronegative group such as F, which disfavors the migration electronically by opposing development of hydridic charge, destabilizes the hydride migration by 1.5 kcal/mol relative to the epimeric exo system. In both ground and transition states the H(m)···H distance decreased with increasing acidity of the proton donor, reaching a minimum of 1.58 Å at the transition state for NH(3)(+). Both Mulliken and NPA charges show enhancement of negative character of the migrating hydride in the cases in which HHH bonding is possible.
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Affiliation(s)
- Simona Marincean
- Natural Sciences Department, University of Michigan-Dearborn, Dearborn, Michigan 48128-1491, United States.
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Time-dependent density functional theory study of the excited-state dihydrogen bonding: clusters of 2-pyridone with diethylmethylsilane and triethylgermanium. J Mol Model 2010; 17:1891-7. [DOI: 10.1007/s00894-010-0896-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2010] [Accepted: 11/03/2010] [Indexed: 12/01/2022]
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An X, Jing B, Li Q. Novel Halogen-Bonded Complexes H3NBH3···XY (XY = ClF, ClCl, BrF, BrCl, and BrBr): Partially Covalent Character. J Phys Chem A 2010; 114:6438-43. [DOI: 10.1021/jp101732c] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Xiulin An
- The Laboratory of Theoretical and Computational Chemistry, Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 264005, People’s Republic of China
| | - Bo Jing
- The Laboratory of Theoretical and Computational Chemistry, Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 264005, People’s Republic of China
| | - Qingzhong Li
- The Laboratory of Theoretical and Computational Chemistry, Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 264005, People’s Republic of China
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Wei N, Li P, Hao C, Wang R, Xiu Z, Chen J, Song P. Time-dependent density functional theory study of the excited-state dihydrogen bond O–H⋯H–Si. J Photochem Photobiol A Chem 2010. [DOI: 10.1016/j.jphotochem.2009.12.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Wei NN, Hao C, Xiu Z, Qiu J. Time-dependent density functional theory study on the coexistent intermolecular hydrogen-bonding and dihydrogen-bonding of the phenol-H2O-diethylmethylsilane complex in electronic excited states. Phys Chem Chem Phys 2010; 12:9445-51. [DOI: 10.1039/b927049c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gao S, Wu W, Mo Y. The B-H...H-P dihydrogen bonding in ion pair complexes [(CF(3))(3)BH(-)][HPH(3-n)(Me)(n)(+)] (n = 0-3) and its implication in H(2) elimination and activation reactions. J Phys Chem A 2009; 113:8108-17. [PMID: 19555090 DOI: 10.1021/jp903059w] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The B-H(delta-)...(delta+)H-P dihydrogen bonding (DHB) in ion pair complexes [(CF(3))(3)BH(-)][HPH(3-n)(Me)(n)(+)] (n = 0-3) and its role in the combination of proton and hydride with the release of H(2) or, reversibly, the heterolytic activation of H(2) by Lewis pairs (CF(3))(3)BPH(3-n)(Me)(n) have been theoretically investigated at the MP2 and DFT levels. It is found that the B-H...H-P bonds behave similarly to those in neutral pairs and ion-molecule complexes in most respects, such as the linearity of the H...H-P moiety, the characteristics of the electron transfer and rearrangement, and the topological properties of the DHB critical point, except that in certain cases, a blue-shifting of the H-bond vibrational frequency is observed. In [(CF(3))(3)BH(-)][HPH(3-n)(Me)(n)(+)], the proton shifting within the complexes leads to the formation of the dihydrogen complex B(CF(3))(3)(eta(2)-H(2)), which is followed by a subsequent H(2) release. The stability of B(CF(3))(3)(eta(2)-H(2)) (D(e)/D(0) = 10.8/6.0 kcal/mol) makes the proton-hydride combination proceed in a fashion similar to the protonation reactions in transition-metal hydrides rather than those in group 13 hydrides EH(4)(-) (E = B, Al, Ga). As for the H(2)-splitting reaction R(3)BPR'(3) + H(2) --> [R(3)BH(-)][HPR'(3)(+)], classical Lewis pair (CLP) (CF(3))(3)BPH(3) exhibits a high barrier and results in an unstable ion pair product [(CF(3))(3)BH(-)][HPH(3)(+)] compared with the "frustrated Lewis pair" (FLP) (C(6)F(5))(3)BP(tBu)(3). A detailed analysis of the mechanistic aspects of H(2) activation by (CF(3))(3)BPH(3) and (C(6)F(5))(3)BP(tBu)(3), supported by another CLP (CF(3))(3)BP(tBu)(3) which has a binding energy comparable to (CF(3))(3)BPH(3) but a reaction exothermicity comparable to (C(6)F(5))(3)BP(tBu)(3), allows us to suggest that the low stability of FLP (C(6)F(5))(3)BP(tBu)(3) is the determining factor for the low reaction barrier. The relative stability and other properties of the ion pair products [R(3)BH(-)][HPR'(3)(+)] have also been analyzed. Results strongly support the view proposed by Rokob et al. [ Rokob , T. A. ; Hamza , A. ; Stirling , A. ; Soos , T. ; Papai , I. Angew. Chem., Int. Ed. 2008 , 47 , 2435 ] that the frustration energy lowers the energy barrier and increases the exothermicity of the reaction.
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Affiliation(s)
- Shulin Gao
- State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
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15
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Filippov OA, Tsupreva VN, Golubinskaya LM, Krylova AI, Bregadze VI, Lledos A, Epstein LM, Shubina ES. Proton-Transfer and H2-Elimination Reactions of Trimethylamine Alane: Role of Dihydrogen Bonding and Lewis Acid−Base Interactions. Inorg Chem 2009; 48:3667-78. [DOI: 10.1021/ic802262h] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Oleg A. Filippov
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia, and Departament de Química, Edifici Cn, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
| | - Victoria N. Tsupreva
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia, and Departament de Química, Edifici Cn, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
| | - Lyudmila M. Golubinskaya
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia, and Departament de Química, Edifici Cn, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
| | - Antonina I. Krylova
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia, and Departament de Química, Edifici Cn, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
| | - Vladimir I. Bregadze
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia, and Departament de Química, Edifici Cn, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
| | - Agusti Lledos
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia, and Departament de Química, Edifici Cn, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
| | - Lina M. Epstein
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia, and Departament de Química, Edifici Cn, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
| | - Elena S. Shubina
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia, and Departament de Química, Edifici Cn, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
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Zhao GJ, Han KL. Novel infrared spectra for intermolecular dihydrogen bonding of the phenol-borane-trimethylamine complex in electronically excited state. J Chem Phys 2007; 127:024306. [PMID: 17640127 DOI: 10.1063/1.2752808] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The intermolecular dihydrogen bonding in the electronically excited states of the dihydrogen-bonded phenol-BTMA complex in gas phase was theoretically investigated using the time-dependent density functional theory method for the first time. It was theoretically demonstrated that the S(1) state of the dihydrogen-bonded phenol-BTMA complex is a locally excited state, in which only the phenol moiety is electronically excited. The infrared spectra of the dihydrogen-bonded phenol-BTMA complex in ground state and the S(1) state were calculated at both the O-H and B-H stretching vibrational regions. A novel infrared spectrum of the dihydrogen-bonded phenol-BTMA complex in the electronically excited state was found. The stretching vibrational absorption bands of the dihydrogen-bonded O-H and B-H groups are very strong in the ground state, while they are disappeared in the S(1) state. At the same time, a new strong absorption band appears at the C[Double Bond]O stretching region. From the calculated bond lengths, it was found that both the O-H and B-H bonds in the dihydrogen bond O-H...H-B are significantly lengthened in the S(1) state of the dihydrogen-bonded phenol-BTMA complex. However, the C-O bond in the phenol moiety is markedly shortened in the excited state, and then has the characteristics of C[Double Bond]O group. Furthermore, it was demonstrated that the intermolecular dihydrogen bonds in the electronically excited state of the dihydrogen-bonded phenol-BTMA complex are strengthened, since calculated H...H distance is drastically shortened in the S(1) state.
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Affiliation(s)
- Guang-Jiu Zhao
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China
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Filippov OA, Filin AM, Tsupreva VN, Belkova NV, Lledós A, Ujaque G, Epstein LM, Shubina ES. Proton-transfer and H2-elimination reactions of main-group hydrides EH4- (E = B, Al, Ga) with alcohols. Inorg Chem 2007; 45:3086-96. [PMID: 16562965 DOI: 10.1021/ic052028n] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The reaction of the isostructural anions of group 13 hydrides EH4- (E = B, Al, Ga) with proton donors of different strength (CH3OH, CF3CH2OH, and CF3OH) was studied with different theoretical methods [DFT/B3LYP and second-order Møller-Plesset (MP2) using the 6-311++G(d,p) basis set]. The results show the general mechanism of the reaction: the dihydrogen-bonded (DHB) adduct (EH...HO) formation leads through the activation barrier to the next concerted step of H2 elimination and alkoxo product formation. The structures, interaction energies (calculated by different approaches including the energy decomposition analysis), vibrational E-H modes, and electron-density distributions were analyzed for all of the DHB adducts. The transition state (TS) is the dihydrogen complex stabilized by a hydrogen bond with the anion [EH3(eta2-H2)...OR-]. The single exception is the reaction of BH4- with CF3OH exhibiting two TSs separated by a shallow minimum of the BH3(eta2-H2)...OR- intermediate. The structures and energies of all of the species were calculated, leading to the establishment of the potential energy profiles for the reaction. A comparison is made with the mechanism of the proton-transfer reaction to transition-metal hydrides. The solvent influence on the stability of all of the species along the reaction pathway was accounted for by means of polarizable conductor calculation model calculations in tetrahydrofuran (THF). Although in THF the DHB intermediates, the TSs, and the products are destabilized with respect to the separated reactants, the energy barriers for the proton transfer are only slightly affected by the solvent. The dependence of the energies of the DHB complexes, TSs, and products as well as the energy barriers for the H2 release on the central atom and the proton donor strength is also discussed.
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Affiliation(s)
- Oleg A Filippov
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 28 Vavilov strasse, 119991 Moscow, Russia
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Ishikawa H, Saito A, Sugiyama M, Mikami N. First observation of a dihydrogen bond involving the Si–H group in phenol-diethylmethylsilane clusters by infrared-ultraviolet double-resonance spectroscopy. J Chem Phys 2005; 123:224309. [PMID: 16375478 DOI: 10.1063/1.2136153] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have experimentally identified a dihydrogen bond involving the Si-H group in phenol-diethylmethylsilane (DEMS) clusters for the first time by IR-UV double-resonance spectroscopy. Vibrational shifts to lower frequency of 21-29 cm(-1) were found for the OH stretching vibration of three isomers of the phenol-DEMS clusters. Spectral simulations based on the MP2 calculations also support our observation. In addition to these clusters, dihydrogen bonds were also observed in the phenol-H(2)O-DEMS and (phenol)(2)-DEMS clusters, which exhibited much stronger interactions than the phenol-DEMS clusters.
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Affiliation(s)
- Haruki Ishikawa
- Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku, Sendai 980-8578, Japan.
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