1
|
Sanderson HJ, Kociok-Köhn G, McMullin CL, Hintermair U. Twinned versus linked organometallics - bimetallic "half-baguette" pentalenide complexes of Rh(I). Dalton Trans 2024; 53:5881-5899. [PMID: 38446046 DOI: 10.1039/d3dt04325h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
The application of Mg[Ph4Pn] and Li·K[Ph4Pn] in transmetalation reactions to a range of Rh(I) precursors led to the formation of "half-baguette" anti-[RhI(L)n]2[μ:η5:η5Ph4Pn] (L = 1,5-cyclooctadiene, norbornadiene, ethylene; n = 1, 2) and syn-[RhI(CO)2]2[μ:η5:η5Ph4Pn] complexes as well as the related iridium complex anti-[IrI(COD)]2[μ:η5:η5Ph4Pn]. With CO exclusive syn metalation was obtained even when using mono-nuclear Rh(I) precursors, indicating an electronic preference for syn metalation. DFT analysis showed this to be the result of π overlap between the adjacent M(CO)2 units which overcompensates for dz2 repulsion of the metals, an effect which can be overridden by steric clash of the auxiliary ligands to yield anti-configuration as seen in the larger olefin complexes. syn-[RhI(CO)2]2[μ:η5:η5Ph4Pn] is a rare example of a twinned organometallic where the two metals are held flexibly in close proximity, but the two d8 Rh(I) centres did not show signs of M-M bonding interactions or exhibit Lewis basic behaviour as in some related mono-nuclear Cp complexes due to the acceptor properties of the ligands. The ligand substitution chemistry of syn-[RhI(CO)2]2[μ:η5:η5Ph4Pn] was investigated with a series of electronically and sterically diverse donor ligands (P(OPh)3, P(OMe)3, PPh3, PMe3, dppe) yielding new mono- and bis-substituted complexes, with E-syn-[RhI(CO)(P{OR})3]2[μ:η5:η5Ph4Pn] (R = Me, Ph) characterised by XRD.
Collapse
Affiliation(s)
- Hugh J Sanderson
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| | - Gabriele Kociok-Köhn
- Material and Chemical Characterisation Facility, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | - Claire L McMullin
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| | - Ulrich Hintermair
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
- Institute for Sustainability, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| |
Collapse
|
2
|
Duncan Lyngdoh RH, Schaefer HF, King RB. Metal-Metal (MM) Bond Distances and Bond Orders in Binuclear Metal Complexes of the First Row Transition Metals Titanium Through Zinc. Chem Rev 2018; 118:11626-11706. [PMID: 30543419 DOI: 10.1021/acs.chemrev.8b00297] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This survey of metal-metal (MM) bond distances in binuclear complexes of the first row 3d-block elements reviews experimental and computational research on a wide range of such systems. The metals surveyed are titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, and zinc, representing the only comprehensive presentation of such results to date. Factors impacting MM bond lengths that are discussed here include (a) the formal MM bond order, (b) size of the metal ion present in the bimetallic core (M2) n+, (c) the metal oxidation state, (d) effects of ligand basicity, coordination mode and number, and (e) steric effects of bulky ligands. Correlations between experimental and computational findings are examined wherever possible, often yielding good agreement for MM bond lengths. The formal bond order provides a key basis for assessing experimental and computationally derived MM bond lengths. The effects of change in the metal upon MM bond length ranges in binuclear complexes suggest trends for single, double, triple, and quadruple MM bonds which are related to the available information on metal atomic radii. It emerges that while specific factors for a limited range of complexes are found to have their expected impact in many cases, the assessment of the net effect of these factors is challenging. The combination of experimental and computational results leads us to propose for the first time the ranges and "best" estimates for MM bond distances of all types (Ti-Ti through Zn-Zn, single through quintuple).
Collapse
Affiliation(s)
| | - Henry F Schaefer
- Centre for Computational Quantum Chemistry , University of Georgia , Athens , Georgia 30602 , United States
| | - R Bruce King
- Centre for Computational Quantum Chemistry , University of Georgia , Athens , Georgia 30602 , United States
| |
Collapse
|
3
|
Labrum NS, Losovyj Y, Caulton KG. A new access route to dimetal sandwich complexes, including a radical anion. Chem Commun (Camb) 2018; 54:12397-12399. [PMID: 30328415 DOI: 10.1039/c8cc05204b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The amide in Cr[N(SiMe3)2]2(THF)2 is displaced by equimolar [K(18-crown-6)][naphthalene] to form the dimetal sandwich Cr2(naphthalene)2- as a radical anion paired with [K(18-crown-6)]+. Two Cr atoms in the sandwich do not form any multiple Cr/Cr bonds, and instead each interacts with one naphthalene in an η6 fashion and with the second naphthalene in an η4 connectivity mode. The naphthalene C/C distances show the effect of back donation from two chromium atoms to a greater extent than simply by 1 electron ring reduction, in comparison to the naphthalene radical anion. The SOMO of the product was established by variable temperature EPR spectroscopy, and the atom ratios and elemental purity were supported by XPS. The possible generality of the displacement of N(SiMe3)2- from a low valent metal is discussed.
Collapse
|
4
|
|
5
|
Cloke FGN, Green JC, Kilpatrick AF, O'Hare D. Bonding in pentalene complexes and their recent applications. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2016.12.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
6
|
Kilpatrick AFR, Green JC, Cloke FGN. Reactivity of a Dititanium Bis(pentalene) Complex toward Heteroallenes and Main-Group Element–Element Bonds. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00791] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexander F. R. Kilpatrick
- Department of Chemistry,
School of Life Sciences, University of Sussex, Brighton BN1 9QJ, United Kingdom
| | - Jennifer C. Green
- Department of Chemistry, University of Oxford, Inorganic Chemistry
Laboratory, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - F. Geoffrey N. Cloke
- Department of Chemistry,
School of Life Sciences, University of Sussex, Brighton BN1 9QJ, United Kingdom
| |
Collapse
|
7
|
Bensalem N, Zouchoune B. Coordination capabilities of anthracene ligand in binuclear sandwich complexes: DFT investigation. Struct Chem 2016. [DOI: 10.1007/s11224-016-0798-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
8
|
Zendaoui SM, Saillard JY, Zouchoune B. Ten-Electron Donor Indenyl Anion in Binuclear Transition-Metal Sandwich Complexes: Electronic Structure and Bonding Analysis. ChemistrySelect 2016. [DOI: 10.1002/slct.201600309] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Saber-Mustapha Zendaoui
- Laboratoire de Chimie Appliquée et Technologie des Matériaux; Université Larbi Ben M'Hidi - Oum El Bouaghi; 04000 Oum El Bouaghi Algeria
- Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale; Université de Constantine; 25000 Constantine Algeria
| | - Jean-Yves Saillard
- Institut des Sciences Chimiques de Rennes; UMR-CNRS 6226; Université de Rennes 1; 35042 Rennes-Cedex France
| | - Bachir Zouchoune
- Laboratoire de Chimie Appliquée et Technologie des Matériaux; Université Larbi Ben M'Hidi - Oum El Bouaghi; 04000 Oum El Bouaghi Algeria
- Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale; Université de Constantine; 25000 Constantine Algeria
| |
Collapse
|
9
|
The Covalent Bond Classification Method and Its Application to Compounds That Feature 3-Center 2-Electron Bonds. THE CHEMICAL BOND III 2016. [DOI: 10.1007/430_2015_206] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
10
|
Yan X, Li X, Sun Z, Li Q, Meng L. Dinuclear first-row transition metal–(C8Me6)2complexes: metal–metal and metal–ligand bonds determined by the d electron configuration of the metal atom. NEW J CHEM 2016. [DOI: 10.1039/c5nj02469b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The nature and strength of the metal–metal and metal–ligand bonds depend on the d electron configuration of the transition metal.
Collapse
Affiliation(s)
- Xiuli Yan
- College of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- China
- Key Laboratory of Inorganic Nano-materials of Hebei Province
| | - Xiaoyan Li
- College of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- China
- Key Laboratory of Inorganic Nano-materials of Hebei Province
| | - Zheng Sun
- College of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- China
- Key Laboratory of Inorganic Nano-materials of Hebei Province
| | - Qingzhong Li
- The Laboratory of Theoretical and Computational Chemistry
- Science and Engineering College of Chemistry and Biology
- Yantai University
- Yantai
- China
| | - Lingpeng Meng
- College of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- China
- Key Laboratory of Inorganic Nano-materials of Hebei Province
| |
Collapse
|
11
|
Kilpatrick AR, Green JC, Cloke FGN. The Reductive Activation of CO 2 Across a Ti=Ti Double Bond: Synthetic, Structural, and Mechanistic Studies. Organometallics 2015; 34:4816-4829. [PMID: 26538790 PMCID: PMC4623487 DOI: 10.1021/acs.organomet.5b00315] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Indexed: 11/29/2022]
Abstract
The reactivity of the bis(pentalene)dititanium double-sandwich compound Ti2Pn†2 (1) (Pn† = 1,4-{SiiPr3}2C8H4) with CO2 is investigated in detail using spectroscopic, X-ray crystallographic, and computational studies. When the CO2 reaction is performed at -78 °C, the 1:1 adduct 4 is formed, and low-temperature spectroscopic measurements are consistent with a CO2 molecule bound symmetrically to the two Ti centers in a μ:η2,η2 binding mode, a structure also indicated by theory. Upon warming to room temperature the coordinated CO2 is quantitatively reduced over a period of minutes to give the bis(oxo)-bridged dimer 2 and the dicarbonyl complex 3. In situ NMR studies indicated that this decomposition proceeds in a stepwise process via monooxo (5) and monocarbonyl (7) double-sandwich complexes, which have been independently synthesized and structurally characterized. 5 is thermally unstable with respect to a μ-O dimer in which the Ti-Ti bond has been cleaved and one pentalene ligand binds in an η8 fashion to each of the formally TiIII centers. The molecular structure of 7 shows a "side-on" bound carbonyl ligand. Bonding of the double-sandwich species Ti2Pn2 (Pn = C8H6) to other fragments has been investigated by density functional theory calculations and fragment analysis, providing insight into the CO2 reaction pathway consistent with the experimentally observed intermediates. A key step in the proposed mechanism is disproportionation of a mono(oxo) di-TiIII species to yield di-TiII and di-TiIV products. 1 forms a structurally characterized, thermally stable CS2 adduct 8 that shows symmetrical binding to the Ti2 unit and supports the formulation of 4. The reaction of 1 with COS forms a thermally unstable complex 9 that undergoes scission to give mono(μ-S) mono(CO) species 10. Ph3PS is an effective sulfur transfer agent for 1, enabling the synthesis of mono(μ-S) complex 11 with a double-sandwich structure and bis(μ-S) dimer 12 in which the Ti-Ti bond has been cleaved.
Collapse
Affiliation(s)
| | - Jennifer C. Green
- Department
of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, U.K.
| | - F. Geoffrey N. Cloke
- Department
of Chemistry, School of Life Sciences, University
of Sussex, Brighton BN1 9QJ, U.K.
| |
Collapse
|
12
|
Kilpatrick AR, Green JC, Cloke FGN. Bonding in Complexes of Bis(pentalene)dititanium, Ti 2(C 8H 6) 2. Organometallics 2015; 34:4830-4843. [PMID: 26538791 PMCID: PMC4623488 DOI: 10.1021/acs.organomet.5b00363] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Indexed: 11/29/2022]
Abstract
Bonding in the bis(pentalene)dititanium "double-sandwich" species Ti2Pn2 (Pn = C8H6) and its interaction with other fragments have been investigated by density functional calculations and fragment analysis. Ti2Pn2 with C2v symmetry has two metal-metal bonds and a low-lying metal-based empty orbital, all three frontier orbitals having a1 symmetry. The latter may be regarded as being derived by symmetric combinations of the classic three frontier orbitals of two bent bis(cyclopentadienyl) metal fragments. Electrochemical studies on Ti2Pn†2 (Pn† = 1,4-{SiiPr3}2C8H4) revealed a one-electron oxidation, and the formally mixed-valence Ti(II)-Ti(III) cationic complex [Ti2Pn†2][B(C6F5)4] has been structurally characterized. Theory indicates an S = 1/2 ground-state electronic configuration for the latter, which was confirmed by EPR spectroscopy and SQUID magnetometry. Carbon dioxide binds symmetrically to Ti2Pn2, preserving the C2v symmetry, as does carbon disulfide. The dominant interaction in Ti2Pn2CO2 is σ donation into the LUMO of bent CO2, and donation from the O atoms to Ti2Pn2 is minimal, whereas in Ti2Pn2CS2 there is significant interaction with the S atoms. The bridging O atom in the mono(oxo) species Ti2Pn2O, however, employs all three O 2p orbitals in binding and competes strongly with Pn, leading to weaker binding of the carbocyclic ligand, and the sulfur analogue Ti2Pn2S behaves similarly. Ti2Pn2 is also capable of binding one, two, or three molecules of carbon monoxide. The bonding demands of a single CO molecule are incompatible with symmetric binding, and an asymmetric structure is found. The dicarbonyl adduct Ti2Pn2(CO)2 has Cs symmetry with the Ti2Pn2 unit acting as two MCp2 fragments. Synthetic studies showed that in the presence of excess CO the tricarbonyl complex Ti2Pn†2(CO)3 is formed, which optimizes to an asymmetric structure with one semibridging and two terminal CO ligands. Low-temperature 13C NMR spectroscopy revealed a rapid dynamic exchange between the two bound CO sites and free CO.
Collapse
Affiliation(s)
| | - Jennifer C. Green
- Department
of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, U.K.
| | - F. Geoffrey N. Cloke
- Department
of Chemistry, School of Life Sciences, University
of Sussex, Brighton BN1 9QJ, U.K.
| |
Collapse
|
13
|
Eisenhart RJ, Rudd PA, Planas N, Boyce DW, Carlson RK, Tolman WB, Bill E, Gagliardi L, Lu CC. Pushing the Limits of Delta Bonding in Metal-Chromium Complexes with Redox Changes and Metal Swapping. Inorg Chem 2015; 54:7579-92. [PMID: 26168331 PMCID: PMC5960016 DOI: 10.1021/acs.inorgchem.5b01163] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Into the metalloligand Cr[N(o-(NCH2P((i)Pr)2)C6H4)3] (1, CrL) was inserted a second chromium atom to generate the dichromium complex Cr2L (2), which is a homobimetallic analogue of the known MCrL complexes, where M is manganese (3) or iron (4). The cationic and anionic counterparts, [MCrL](+) and [MCrL](-), respectively, were targeted, and each MCr pair was isolated in at least one other redox state. The solid-state structures of the [MCrL](+,0,-) redox members are essentially the same, with ultrashort metal-metal bonds between 1.96 and 1.74 Å. The formal shortness ratios (r) of these interactions are between 0.84 and 0.74 and are interpreted as triple to quintuple metal-metal bonds with the aid of theory. The trio of (d-d)(10) species [Cr2L](-) (2(red)), MnCrL (3), and [FeCrL](+) (4(ox)) are S = 0 diamagnets. On the basis of M-Cr bond distances and theoretical calculations, the strength of the metal-metal bond across the (d-d)(10) series increases in the order Fe < Mn < Cr. The methylene protons in the ligand are shifted downfield in the (1)H NMR spectra, and the diamagnetic anisotropy of the metal-metal bond was calculated as -3500 × 10(-36), -3900 × 10(-36), and -5800 × 10(-36) m(3) molecule(-1) for 2(red), 3, and 4(ox) respectively. The magnitude of diamagnetic anisotropy is, thus, affected more by bond polarity than by bond order. A comparative vis-NIR study of quintuply bonded 2(red) and 3 revealed a large red shift in the δ(4) → δ(3)δ* transition energy upon swapping from the (Cr2)(2+) to the (MnCr)(3+) core. Complex 2(red) was further investigated by resonance Raman spectroscopy, and a band at 434 cm(-1) was assigned as the Cr-Cr bond vibration. Finally, 4(ox) exhibited a Mössbauer doublet with an isomer shift of 0.18 mm/s that suggests a primarily Fe-based oxidation to Fe(I).
Collapse
Affiliation(s)
- Reed J. Eisenhart
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - P. Alex Rudd
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Nora Planas
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Supercomputing Institute and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - David W. Boyce
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Rebecca K. Carlson
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Supercomputing Institute and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - William B. Tolman
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Eckhard Bill
- Max Planck Institut für Chemische Energiekonversion (MPI-CEC), Stiftstraße 34–36, 45470 Mülheim an der Ruhr, Germany
| | - Laura Gagliardi
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Supercomputing Institute and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Connie C. Lu
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
14
|
Wang H, Wang H, King RB, Schaefer HF. Bis(azulene) “submarine” metal dimer sandwich compounds (C10H8)2M2(M = Ti, V, Cr, Mn, Fe, Co, Ni): Parallel and opposed orientations. J Comput Chem 2015. [DOI: 10.1002/jcc.24013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Hongyan Wang
- School of Physical Science and Technology; Southwest Jiaotong University
- Key Laboratory of Advanced Technologies of Materials; Ministry of Education of China; Chengdu 610031 China
| | - Hui Wang
- School of Physical Science and Technology; Southwest Jiaotong University
- Key Laboratory of Advanced Technologies of Materials; Ministry of Education of China; Chengdu 610031 China
| | - R. Bruce King
- Department of Chemistry and Center for Computational Chemistry; University of Georgia; Athens Georgia 30602
| | - Henry F. Schaefer
- Department of Chemistry and Center for Computational Chemistry; University of Georgia; Athens Georgia 30602
| |
Collapse
|
15
|
Coordination diversity of the phenazine ligand in binuclear transition metal sandwich complexes: Theoretical investigation. J Organomet Chem 2014. [DOI: 10.1016/j.jorganchem.2014.07.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
16
|
Kilpatrick AFR, Cloke FGN. Reductive deoxygenation of CO2 by a bimetallic titanium bis(pentalene) complex. Chem Commun (Camb) 2014; 50:2769-71. [DOI: 10.1039/c3cc48379g] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The bimetallic bis(pentalene) complex Ti2(μ:η5,η5-C8H4{SiiPr3-1,4}2)2 reduces CO2 to afford dicarbonyl and bridging oxo-complexes.
Collapse
|
17
|
Liu YC, Wu SX, Su ZM, Zhang HY. Can a linear metal–metal bonded array of tetravanadium be stabilized between two dicyclopenta[a,e]pentalene ligands? A theoretical investigation. NEW J CHEM 2014. [DOI: 10.1039/c3nj00857f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
18
|
A new heterobimetallic manganese–rhodium carbonyl complex derived from partially alkylated s-indacene. Inorganica Chim Acta 2013. [DOI: 10.1016/j.ica.2012.08.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
19
|
Kilpatrick AFR, Green JC, Cloke FGN, Tsoureas N. Bis(pentalene)di-titanium: a bent double-sandwich complex with a very short Ti–Ti bond. Chem Commun (Camb) 2013; 49:9434-6. [PMID: 24005653 DOI: 10.1039/c3cc45187a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
|
20
|
Summerscales OT, Rivers CJ, Taylor MJ, Hitchcock PB, Green JC, Cloke FGN. Double-Sandwich Pentalene Complexes M2(pent†)2 (M = Rh, Pd; pent† = 1,4-Bis(triisopropylsilyl)pentalene): Synthesis, Structure, and Bonding. Organometallics 2012. [DOI: 10.1021/om3010004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Owen T. Summerscales
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, U.K
| | - Christopher J. Rivers
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, U.K
| | - Morgan J. Taylor
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, U.K
| | - Peter B. Hitchcock
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, U.K
| | - Jennifer C. Green
- Inorganic Chemistry Laboratory, Chemistry Department, Oxford University, South Parks Road, Oxford OX1 3QR,
U.K
| | - F. Geoffrey N. Cloke
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, U.K
| |
Collapse
|
21
|
Li H, Feng H, Sun W, Fan Q, Xie Y, King RB, Schaefer HF. Bis(heptalene) "submarine" metal dimer sandwich compounds (C12H10)2M2 (M = Ti, V, Cr, Mn, Fe, Co, Ni). J Mol Model 2012; 19:2723-37. [PMID: 22890748 DOI: 10.1007/s00894-012-1540-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 07/16/2012] [Indexed: 10/28/2022]
Abstract
The bis(heptalene)dimetal complexes (C12H10)2M2 of the first row transition metals from Ti to Ni are predicted by density functional theory to exhibit "submarine" sandwich structures with a pair of metal atoms sandwiched between the two heptalene rings. For the early transition metal derivatives (C12H10)2M2 (M = V, Cr) there are two types of such structures. In one structural type the metals are sandwiched between two heptahapto heptalene rings with metal-metal distances (3.5-3.8 Å) too long for direct metal-metal bonding. The other type of (C12H10)2M2 (M = V, Cr, Mn) structure has a pair of bonded metal atoms sandwiched between a fully bonded heptalene ligand and a heptalene ligand bonded to the metals only through an eight-carbon heptafulvene subunit, leaving an uncomplexed cis-1,3-diene unit. The formal metal-metal bond orders in these latter structures are 3, 2, and 1 for M = V, Cr, and Mn with predicted bond lengths of 2.5, 2.7, and 2.8 Å, respectively. For (C12H10)2Fe2 a singlet structure with each iron atom sandwiched between a hexahapto and a tetrahapto heptalene ring is energetically preferred over an alternate structure with ferrocene-like iron atoms sandwiched between two pentahapto heptalene rings. Partial bonding of each heptalene ring to the metal atoms occurs in the late transition metal derivatives (C12H10)2M2 (M = Co, Ni). This leads to an unsymmetrical structure for the cobalt derivative and a structure for the nickel derivative with each nickel atom sandwiched between a trihapto ligand and a tetrahapto ligand.
Collapse
Affiliation(s)
- Huidong Li
- School of Physics and Chemistry, Research Center for Advanced Computation, Xihua University, Chengdu, 610039, China
| | | | | | | | | | | | | |
Collapse
|
22
|
Green JC, Green MLH, Parkin G. The occurrence and representation of three-centre two-electron bonds in covalent inorganic compounds. Chem Commun (Camb) 2012; 48:11481-503. [DOI: 10.1039/c2cc35304k] [Citation(s) in RCA: 222] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
23
|
Halcrow MA. Structure:function relationships in molecular spin-crossover complexes. Chem Soc Rev 2011; 40:4119-42. [PMID: 21483934 DOI: 10.1039/c1cs15046d] [Citation(s) in RCA: 642] [Impact Index Per Article: 49.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Spin-crossover compounds are becoming increasingly popular for device and sensor applications, and in soft materials, that make use of their switchable colour, paramagnetism and conductivity. The de novo design of new solid spin-crossover compounds with pre-defined switching properties is desirable for application purposes. This challenging problem of crystal engineering requires an understanding of how the temperature and cooperativity of a spin-transition are influenced by the structure of the bulk material. Towards that end, this critical review presents a survey of molecular spin-crossover compounds with good availability of crystallographic data. A picture is emerging that changes in molecular shape between the high- and low-spin states, and the ability of a lattice to accommodate such changes, can play an important role in determining the existence and the cooperativity of a thermal spin-transition in the solid state (198 references).
Collapse
Affiliation(s)
- Malcolm A Halcrow
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, UK LS2 9JT. m.a.halcrow@ leeds.ac.uk
| |
Collapse
|
24
|
|
25
|
Aguirre-Etcheverry P, O’Hare D. Electronic Communication through Unsaturated Hydrocarbon Bridges in Homobimetallic Organometallic Complexes. Chem Rev 2010; 110:4839-64. [DOI: 10.1021/cr9003852] [Citation(s) in RCA: 289] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Paulina Aguirre-Etcheverry
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA
| | - Dermot O’Hare
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA
| |
Collapse
|
26
|
Cramer CJ, Truhlar DG. Density functional theory for transition metals and transition metal chemistry. Phys Chem Chem Phys 2009; 11:10757-816. [PMID: 19924312 DOI: 10.1039/b907148b] [Citation(s) in RCA: 1079] [Impact Index Per Article: 71.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We introduce density functional theory and review recent progress in its application to transition metal chemistry. Topics covered include local, meta, hybrid, hybrid meta, and range-separated functionals, band theory, software, validation tests, and applications to spin states, magnetic exchange coupling, spectra, structure, reactivity, and catalysis, including molecules, clusters, nanoparticles, surfaces, and solids.
Collapse
Affiliation(s)
- Christopher J Cramer
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, MN 55455-0431, USA.
| | | |
Collapse
|
27
|
Affiliation(s)
- Xiaojun Wu
- Department of Chemistry and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588
| | - Xiao Cheng Zeng
- Department of Chemistry and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588
| |
Collapse
|
28
|
Ashley AE, Cooper RT, Wildgoose GG, Green JC, O'Hare D. Homoleptic permethylpentalene complexes: "double metallocenes" of the first-row transition metals. J Am Chem Soc 2008; 130:15662-77. [PMID: 18939834 DOI: 10.1021/ja8057138] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis of the bimetallic permethylpentalene complexes Pn*2M2 (M = V, Cr, Mn, Co, Ni; Pn* = C8Me6) has been accomplished, and all of the complexes have been structurally characterized in the solid state by single-crystal X-ray diffraction. Pn*2V2 (1) and Pn*2Mn2 (3) show very short intermetallic distances that are consistent with metal-metal bonding, while the cobalt centers in Pn*2Co2 (4) exhibit differential bonding to each side of the Pn* ligand that is consistent with an eta(5):eta(3) formulation. The Pn* ligands in Pn*2Ni2 (5) are best described as eta(3):eta(3)-bonded to the metal centers. (1)H NMR studies indicate that all of the Pn*2M2 species exhibit D(2h) molecular symmetry in the solution phase; the temperature variation of the chemical shifts for the resonances of Pn*2Cr2 (2) indicates that the molecule has an S = 0 ground state and a thermally populated S = 1 excited state and can be successfully modeled using a Boltzmann distribution (DeltaH(o) = 14.9 kJ mol(-1) and DeltaS(o) = 26.5 J K(-1) mol(-1)). The solid-state molar magnetic susceptibility of 3 obeys the Curie-Weiss law with mu(eff) = 2.78 muB and theta = -1.0 K; the complex is best described as having an S = 1 electronic ground state over the temperature range 4-300 K. Paradoxically, attempts to isolate the "double ferrocene" equivalent, Pn*2Fe2, led only to the isolation of the permethylpentalene dimer Pn*2 (6). Solution electrochemical studies were performed on all of the organometallic compounds; 2-5 exhibit multiple quasi-reversible redox processes. Density functional theory calculations were performed on this series of complexes in order to rationalize the observed structural and spectroscopic data and provide estimates of the M-M bond orders.
Collapse
Affiliation(s)
- Andrew E Ashley
- Chemistry Research Laboratory, Oxford University, Mansfield Rd, Oxford OX1 3TA, UK
| | | | | | | | | |
Collapse
|