1
|
Asatryan R, Pal Y, Hachmann J, Ruckenstein E. Roaming-like Mechanism for Dehydration of Diol Radicals. J Phys Chem A 2018; 122:9738-9754. [DOI: 10.1021/acs.jpca.8b08690] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rubik Asatryan
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Yudhajit Pal
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
- Computational and Data-Enabled Science and Engineering Graduate Program, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Johannes Hachmann
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
- New York State Center of Excellence in Materials Informatics, Buffalo, New York 14203, United States
- Computational and Data-Enabled Science and Engineering Graduate Program, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Eli Ruckenstein
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| |
Collapse
|
2
|
Asatryan R, Ruckenstein E, Hachmann J. Revisiting the polytopal rearrangements in penta-coordinate d 7-metallocomplexes: modified Berry pseudorotation, octahedral switch, and butterfly isomerization. Chem Sci 2017; 8:5512-5525. [PMID: 28970931 PMCID: PMC5618771 DOI: 10.1039/c7sc00703e] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 05/26/2017] [Indexed: 11/28/2022] Open
Abstract
This paper provides a first-principles theoretical investigation of the polytopal rearrangements and fluxional behavior of five-coordinate d7-transition metal complexes. Our work is primarily based on a potential energy surface analysis of the iron tetracarbonyl hydride radical HFe˙(CO)4. We demonstrate the existence of distorted coordination geometries in this prototypical system and, for the first time, introduce three general rearrangement mechanisms, which account for the non-ideal coordination. The first of these mechanisms constitutes a modified version of the Berry pseudorotation via a square-based pyramidal C4v transition state that connects two chemically identical edge-bridged tetrahedral stereoisomers of C2v symmetry. It differs from the classical Berry mechanism, which involves two regular D3h equilibrium structures and a C4v transition state. The second mechanism is related to the famous "tetrahedral jump" hypothesis, postulated by Muetterties for a number of d6 HML4 and H2ML4 complexes. Here, our study suggests two fluxional rearrangement pathways via distinct types of C2v transition states. Both pathways of this mechanism can be described as a single-ligand migration to a vacant position of an "octahedron", thus interchanging (switching) the apical and basal ligands of the initial quasi-square pyramidal isomer, which is considered as an idealized octahedron with a vacancy. Accordingly, we call this mechanism "octahedral switch". The third mechanism follows a butterfly-type isomerization featuring a key-angle deformation, and we thus call it "butterfly isomerization". It connects the quasi-square pyramidal and edge-bridged tetrahedral isomers of HFe˙(CO)4 through a distorted edge-bridged tetrahedral transition state of Cs symmetry. Our paper discusses the overall features of the isomers and rearrangement mechanisms as well as their implications. We rationalize the existence of each stationary point through an electronic structure analysis and argue their relevance for isolobal analogues of HFe˙(CO)4.
Collapse
Affiliation(s)
- Rubik Asatryan
- Department of Chemical and Biological Engineering , University at Buffalo , The State University of New York , Buffalo , NY 14260 , USA . ;
| | - Eli Ruckenstein
- Department of Chemical and Biological Engineering , University at Buffalo , The State University of New York , Buffalo , NY 14260 , USA . ;
| | - Johannes Hachmann
- Department of Chemical and Biological Engineering , University at Buffalo , The State University of New York , Buffalo , NY 14260 , USA . ;
- New York State Center of Excellence in Materials Informatics , Buffalo , NY 14203 , USA
- Computational and Data-Enabled Science and Engineering Graduate Program , University at Buffalo , The State University of New York , Buffalo , NY 14260 , USA
| |
Collapse
|
3
|
Dinda S, Genest A, Rösch N. O2 Activation and Catalytic Alcohol Oxidation by Re Complexes with Redox-Active Ligands: A DFT Study of Mechanism. ACS Catal 2015. [DOI: 10.1021/acscatal.5b00509] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Shrabani Dinda
- Institute of High Performance Computing, Agency for Science, Technology
and Research, 1 Fusionopolis Way, #16-16
Connexis, Singapore 138632, Singapore
| | - Alexander Genest
- Institute of High Performance Computing, Agency for Science, Technology
and Research, 1 Fusionopolis Way, #16-16
Connexis, Singapore 138632, Singapore
| | - Notker Rösch
- Institute of High Performance Computing, Agency for Science, Technology
and Research, 1 Fusionopolis Way, #16-16
Connexis, Singapore 138632, Singapore
- Department Chemie and Catalysis Research
Center, Technische Universität München, 85747 Garching, Germany
| |
Collapse
|
4
|
Olatunji-Ojo OA, Cundari TR. C–H Activation by Multiply Bonded Complexes with Potentially Noninnocent Ligands: A Computational Study. Inorg Chem 2013; 52:8106-13. [DOI: 10.1021/ic400804x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Olayinka A. Olatunji-Ojo
- Department of Chemistry
and Center for Advanced Scientific
Computing and Modeling (CASCaM), University of North Texas, 1155 Union Circle, #305070 Denton, Texas 76203-5070,
United States
| | - Thomas R. Cundari
- Department of Chemistry
and Center for Advanced Scientific
Computing and Modeling (CASCaM), University of North Texas, 1155 Union Circle, #305070 Denton, Texas 76203-5070,
United States
| |
Collapse
|
5
|
Frazier BA, Williams VA, Wolczanski PT, Bart SC, Meyer K, Cundari TR, Lobkovsky EB. C-C bond formation and related reactions at the CNC backbone in (smif)FeX (smif = 1,3-di-(2-pyridyl)-2-azaallyl): dimerizations, 3 + 2 cyclization, and nucleophilic attack; transfer hydrogenations and alkyne trimerization (X = N(TMS)2, dpma = (di-(2-pyridyl-methyl)-amide)). Inorg Chem 2013; 52:3295-312. [PMID: 23448130 DOI: 10.1021/ic302783y] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Molecular orbital analysis depicts the CNC(nb) backbone of the smif (1,3-di-(2-pyridyl)-2-azaallyl) ligand as having singlet diradical and/or ionic character where electrophilic or nucleophilic attack is plausible. Reversible dimerization of (smif)Fe{N(SiMe3)2} (1) to [{(Me3Si)2N}Fe]2(μ-κ(3),κ(3)-N,py2-smif,smif) (2) may be construed as diradical coupling. A proton transfer within the backbone-methylated, and o-pyridine-methylated smif of putative ((b)Me2(o)Me2smif)FeN(SiMe3)2 (8) provides a route to [{(Me3Si)2N}Fe]2(μ-κ(4),κ(4)-N,py2,C-((b)Me,(b)CH2,(o)Me2(smif)H))2 (9). A 3 + 2 cyclization of ditolyl-acetylene occurs with 1, leading to the dimer [{2,5-di(pyridin-2-yl)-3,4-di-(p-tolyl-2,5-dihydropyrrol-1-ide)}FeN(SiMe3)2]2 (11), and the collateral discovery of alkyne cyclotrimerization led to a brief study that identified Fe(N(SiMe3)2(THF) as an effective catalyst. Nucleophilic attack by (smif)2Fe (13) on (t)BuNCO and (2,6-(i)Pr2C6H3)NCO afforded (RNHCO-smif)2Fe (14a, R = (t)Bu; 14b, 2,6-(i)PrC6H3). Calculations suggested that (dpma)2Fe (15) would favorably lose dihydrogen to afford (smif)2Fe (13). H2-transfer to alkynes, olefins, imines, PhN═NPh, and ketones was explored, but only stoichiometric reactions were affected. Some physical properties of the compounds were examined, and X-ray structural studies on several dinuclear species were conducted.
Collapse
Affiliation(s)
- Brenda A Frazier
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA
| | | | | | | | | | | | | |
Collapse
|
6
|
Frazier BA, Wolczanski PT, Keresztes I, DeBeer S, Lobkovsky EB, Pierpont AW, Cundari TR. Synthetic approaches to (smif)2Ti (smif = 1,3-di-(2-pyridyl)-2-azaallyl) reveal redox non-innocence and C-C bond-formation. Inorg Chem 2012; 51:8177-86. [PMID: 22830452 DOI: 10.1021/ic300590t] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Attempted syntheses of (smif)(2)Ti (smif =1,3-di-(2-pyridyl)-2-azaallyl) based on metatheses of TiCl(n)L(m) (n = 2-4) with M(smif) (M = Li, Na), in the presence of a reducing agent (Na/Hg) when necessary, failed, but several apparent Ti(II) species were identified by X-ray crystallography and multidimensional NMR spectroscopy: (smif){Li(smif-smif)}Ti (1, X-ray), [(smif)Ti](2)(μ-κ(3),κ(3)-N,N(py)(2)-smif,smif) (2), (smif)Ti(κ(3)-N,N(py)(2)-smif,(smif)H) (3), and (smif)Ti(dpma) (4, dpma = di-2-pyridylmethyl-amide). NMR spectroscopy and K-edge XAS showed that each compound possesses ligands that are redox noninnnocent, such that d(1) Ti(III) centers AF-couple to ligand radicals: (smif){Li(smif-smif)(2-)}Ti(III) (1), [(smif(2-))Ti(III)](2)(μ-κ(3),κ(3)-N,N(py)(2)-smif,smif) (2), [(smif(2-))Ti(III)](κ(3)-N,N(py)(2)-smif,(smif)H) (3), and (smif(2-))Ti(III)(dpma) (4). The instability of (smif)(2)Ti relative to its C-C coupled dimer, 2, is rationalized via the complementary nature of the amide and smif radical dianion ligands, which are also common to 3 and 4. Calculations support this contention.
Collapse
Affiliation(s)
- Brenda A Frazier
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | | | | | | | | | | | | |
Collapse
|
7
|
Frazier BA, Bartholomew ER, Wolczanski PT, DeBeer S, Santiago-Berrios M, Abruña HD, Lobkovsky EB, Bart SC, Mossin S, Meyer K, Cundari TR. Synthesis and Characterization of (smif)2Mn (n = 0, M = V, Cr, Mn, Fe, Co, Ni, Ru; n = +1, M = Cr, Mn, Co, Rh, Ir; smif =1,3-di-(2-pyridyl)-2-azaallyl). Inorg Chem 2011; 50:12414-36. [DOI: 10.1021/ic200376f] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Brenda A. Frazier
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Erika R. Bartholomew
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Peter T. Wolczanski
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Serena DeBeer
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Mitk’El Santiago-Berrios
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Hector D. Abruña
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Emil B. Lobkovsky
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Suzanne C. Bart
- Department of Chemistry & Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 1, D-91058 Erlangen, Germany
| | - Susanne Mossin
- Department of Chemistry & Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 1, D-91058 Erlangen, Germany
| | - Karsten Meyer
- Department of Chemistry & Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 1, D-91058 Erlangen, Germany
| | - Thomas R. Cundari
- Department of Chemistry, Center
for Advanced Scientific Computing and Modeling (CASCaM), University of North Texas, Box 305070, Denton, Texas
76203-5070, United States
| |
Collapse
|