1
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Gao H, Kwon S, Kwon HY, Irran E, Klare HFT, Baik MH, Oestreich M. Cationic Bis(hydrosilane)-Coinage-Metal Complexes: Synthesis, Characterization, and Use as Catalysts for Outer-Sphere C=O Hydrosilylation Not Involving Metal Hydrides. Angew Chem Int Ed Engl 2024; 63:e202409582. [PMID: 38923659 DOI: 10.1002/anie.202409582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 06/10/2024] [Accepted: 06/24/2024] [Indexed: 06/28/2024]
Abstract
The preparation of cationic bis(hydrosilane)-coinage-metal complexes by chloride abstraction from the neutral metal chloride precursors with Na[BArF 4] is described. Unlike previously reported hydrosilane-stabilized copper and silver complexes, the presented complexes are cationic and feature two bidentate (ortho-silylphenyl)phosphine ligands. These complexes were fully characterized by NMR spectroscopy and X-ray diffraction analysis, revealing that both Si-H bonds are activated by the Lewis acidic cationic metal center. The new complexes were found to be effective in catalytic carbonyl hydrosilylation, leading to the corresponding silyl ethers under mild conditions without the addition of an external base. Combined mechanistic control experiments and quantum chemical calculations support an ionic outer-sphere mechanism, in which a neutral metal alkoxide species instead of a metal hydride is the key intermediate that interacts with the silylcarboxonium ion to generate the silyl ether.
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Affiliation(s)
- Haopeng Gao
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623, Berlin, Germany
| | - Seongyeon Kwon
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS) & Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Hyuk-Yong Kwon
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS) & Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Elisabeth Irran
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623, Berlin, Germany
| | - Hendrik F T Klare
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623, Berlin, Germany
| | - Mu-Hyun Baik
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS) & Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Martin Oestreich
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623, Berlin, Germany
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2
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Laglera-Gándara CJ, Jiménez-Pérez J, Fernández-de-Córdova FJ, Ríos P, Conejero S. Electrophilic Hydrosilylation of Electron-Rich Alkenes Derived from Enamines. Angew Chem Int Ed Engl 2024; 63:e202404859. [PMID: 38634763 DOI: 10.1002/anie.202404859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/16/2024] [Accepted: 04/16/2024] [Indexed: 04/19/2024]
Abstract
The low-electron count, air-stable, platinum complexes [Pt(ItBu')(ItBu)][BArF] (C1) (ItBu=1,3-di-tert-butylimidazol-2-ylidene), [Pt(SiPh)3(ItBuiPr)2][BArF] (C2) (ItBuiPr=1-tert-butyl-3-iso-propylimidazol-2-ylidene), [Pt(SiPh)3(ItBuMe)2][BArF] (C3), [Pt(GePh3)(ItBuiPr)2][BArF] (C4), [Pt(GePh)3(ItBuMe)2][BArF] (C5) and [Pt(GeEt)3(ItBuMe)2][BArF] (C6) (ItBuMe=1-tert-butyl-3-methylimidazol-2-ylidene) are efficient catalysts (particularly the germyl derivatives) in both the silylative dehydrocoupling and hydrosilylation of electron rich alkenes derived from enamines. The steric hindrance exerted by the NHC ligand plays an important role in the selectivity of the reaction. Thus, bulky ligands are selective towards the silylative dehydrocoupling process whereas less sterically hindered promote the selective hydrosilylation reaction. The latter is, in addition, regioselective towards the β-carbon atom of both internal and terminal enamines, leading to β-aminosilanes. Moreover, the syn stereochemistry of the amino and silyl groups implies an anti Si-H bond addition across the double bond. All these facts point to a mechanistic picture that, according to experimental and computational studies, involves a non-classical hydrosilylation process through an outer-sphere mechanism in which a formal nucleophilic addition of the enamine to the silicon atom of a platinum σ-SiH complex is the key step. This is in sharp contrast with the classical Chalk-Harrod mechanism prevalent in platinum chemistry.
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Affiliation(s)
- Carlos J Laglera-Gándara
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
| | - Julián Jiménez-Pérez
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
| | - Francisco J Fernández-de-Córdova
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
| | - Pablo Ríos
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
| | - Salvador Conejero
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
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3
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Cross MJ, Brodie CN, Crivoi DG, Goodall JC, Ryan DE, Martínez‐Martínez AJ, Johnson A, Weller AS. Dehydropolymerization of Amine-Boranes using Bis(imino)pyridine Rhodium Pre-Catalysis: σ-Amine-Borane Complexes, Nanoparticles, and Low Residual-Metal BN-Polymers that can be Chemically Repurposed. Chemistry 2023; 29:e202302110. [PMID: 37530441 PMCID: PMC10947130 DOI: 10.1002/chem.202302110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/31/2023] [Accepted: 08/02/2023] [Indexed: 08/03/2023]
Abstract
The sigma amine-borane complexes [Rh(L1)(η2 :η2 -H3 B⋅NRH2 )][OTf] (L1=2,6-bis-[1-(2,6-diisopropylphenylimino)ethyl]pyridine, R=Me, Et, n Pr) are described, alongside [Rh(L1)(NMeH2 )][OTf]. Using R=Me as a pre-catalyst (1 mol %) the dehydropolymerization of H3 B ⋅ NMeH2 gives [H2 BNMeH]n selectively. Added NMeH2 , or the direct use of [Rh(L1)(NMeH2 )][OTf], is required for initiation of catalysis, which is suggested to operate through the formation of a neutral hydride complex, Rh(L1)H. The formation of small (1-5 nm) nanoparticles is observed at the end of catalysis, but studies are ambiguous as to whether the catalysis is solely nanoparticle promoted or if there is a molecular homogeneous component. [Rh(L1)(NMeH2 )][OTf] is shown to operate at 0.025 mol % loadings on a 2 g scale of H3 B ⋅ NMeH2 to give polyaminoborane [H2 BNMeH]n [Mn =30,900 g/mol, Ð=1.8] that can be purified to a low residual [Rh] (6 μg/g). Addition of Na[N(SiMe3 )2 ] to [H2 BNMeH]n results in selective depolymerization to form the eee-isomer of N,N,N-trimethylcyclotriborazane [H2 BNMeH]3 : the chemical repurposing of a main-group polymer.
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Affiliation(s)
| | | | - Dana G. Crivoi
- Department of ChemistryUniversity of OxfordOxfordOX1 3TAUK
| | | | - David E. Ryan
- Department of ChemistryUniversity of YorkYorkYO10 5DDUK
- Department of ChemistryUniversity of OxfordOxfordOX1 3TAUK
| | - Antonio J. Martínez‐Martínez
- Department of ChemistryUniversity of OxfordOxfordOX1 3TAUK
- Supramolecular Organometallic and Main Group Chemistry Laboratory CIQSO-Center for Research in Sustainable Chemistry and Department of ChemistryUniversity of HuelvaCampus El Carmen21007HuelvaSpain
| | - Alice Johnson
- Department of ChemistryUniversity of OxfordOxfordOX1 3TAUK
- Department of Biosciences and ChemistrySheffield Hallam UniversityHoward StSheffieldS1 1WBUK
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4
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Greßies S, Süße L, Casselman T, Stoltz BM. Tandem Dearomatization/Enantioselective Allylic Alkylation of Pyridines. J Am Chem Soc 2023; 145:11907-11913. [PMID: 37212659 PMCID: PMC10251512 DOI: 10.1021/jacs.3c02470] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Indexed: 05/23/2023]
Abstract
Herein, we report a multistep one-pot reaction of substituted pyridines leading to N-protected tetrahydropyridines with outstanding enantioselectivity (up to 97% ee). An iridium(I)-catalyzed dearomative 1,2-hydrosilylation of pyridines enables the use of N-silyl enamines as a new type of nucleophile in a subsequent palladium-catalyzed asymmetric allylic alkylation. This telescoped process overcomes the intrinsic nucleophilic selectivity of pyridines to synthesize enantioenriched, C-3-substituted tetrahydropyridine products that have been otherwise challenging to access.
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Affiliation(s)
- Steffen Greßies
- Warren and Katharine Schlinger
Laboratory for Chemistry and Chemical Engineering, Division of Chemistry
and Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Lars Süße
- Warren and Katharine Schlinger
Laboratory for Chemistry and Chemical Engineering, Division of Chemistry
and Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Tyler Casselman
- Warren and Katharine Schlinger
Laboratory for Chemistry and Chemical Engineering, Division of Chemistry
and Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Brian M. Stoltz
- Warren and Katharine Schlinger
Laboratory for Chemistry and Chemical Engineering, Division of Chemistry
and Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
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5
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Stevens JE, Moore CE, Thomas CM. Si-H Bond Activation and Dehydrogenative Coupling of Silanes across the Iron-Amide Bond of a Bis(amido)bis(phosphine) Iron(II) Complex. J Am Chem Soc 2023; 145:794-799. [PMID: 36594789 DOI: 10.1021/jacs.2c12157] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Despite the utility of Si-Si bonds, there are relatively few examples of Si-Si bond formation by base metals. In this work, a four-coordinate iron complex, (PNNP)FeII, is shown to strongly activate the Si-H bonds in primary silanes across the Fe-amide bonds in a metal-ligand cooperative fashion. Upon treatment with excess silane, Si-Si dehydrogenative homocoupling is shown to occur across the Fe-Namide bond without concomitant oxidation and spin state changes at the Fe center.
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Affiliation(s)
- Jeremiah E Stevens
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, Ohio 43210, United States
| | - Curtis E Moore
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, Ohio 43210, United States
| | - Christine M Thomas
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, Ohio 43210, United States
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6
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Jiang HJ, Simon HDA, Irran E, Klare HFT, Oestreich M. Experimental Mechanistic Analysis of Carbonyl Hydrosilylation Catalyzed by Abu-Omar’s Rhenium(V) Oxo Complex. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Hua-Jie Jiang
- Institut für Chemie, Technische Universitat Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Hendrik D. A. Simon
- Institut für Chemie, Technische Universitat Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Elisabeth Irran
- Institut für Chemie, Technische Universitat Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Hendrik F. T. Klare
- Institut für Chemie, Technische Universitat Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Martin Oestreich
- Institut für Chemie, Technische Universitat Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
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7
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Guzmán J, Urriolabeitia A, Padilla M, García-Orduña P, Polo V, Fernández-Alvarez FJ. Mechanism Insights into the Iridium(III)- and B(C 6F 5) 3-Catalyzed Reduction of CO 2 to the Formaldehyde Level with Tertiary Silanes. Inorg Chem 2022; 61:20216-20221. [PMID: 36472385 PMCID: PMC10468102 DOI: 10.1021/acs.inorgchem.2c03330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Indexed: 12/12/2022]
Abstract
The catalytic system [Ir(CF3CO2)(κ2-NSiMe)2] [1; NSiMe = (4-methylpyridin-2-yloxy)dimethylsilyl]/B(C6F5)3 promotes the selective reduction of CO2 with tertiary silanes to the corresponding bis(silyl)acetal. Stoichiometric and catalytic studies evidenced that species [Ir(CF3COO-B(C6F5)3)(κ2-NSiMe)2] (3), [Ir(κ2-NSiMe)2][HB(C6F5)3] (4), and [Ir(HCOO-B(C6F5)3)(κ2-NSiMe)2] (5) are intermediates of the catalytic process. The structure of 3 has been determined by X-ray diffraction methods. Theoretical calculations show that the rate-limiting step for the 1/B(C6F5)3-catalyzed hydrosilylation of CO2 to bis(silyl)acetal is a boron-promoted Si-H bond cleavage via an iridium silylacetal borane adduct.
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Affiliation(s)
- Jefferson Guzmán
- Facultad
de Ciencias, Departamento de Química Inorgánica, Instituto
de Síntesis Química y Catálisis Homogénea, Universidad de Zaragoza, CSIC, Zaragoza 50009, Spain
| | - Asier Urriolabeitia
- Facultad
de Ciencias, Departamento de Química Física, BIFI, Universidad de Zaragoza, Zaragoza 50009, Spain
| | - Marina Padilla
- Facultad
de Ciencias, Departamento de Química Inorgánica, Instituto
de Síntesis Química y Catálisis Homogénea, Universidad de Zaragoza, CSIC, Zaragoza 50009, Spain
| | - Pilar García-Orduña
- Facultad
de Ciencias, Departamento de Química Inorgánica, Instituto
de Síntesis Química y Catálisis Homogénea, Universidad de Zaragoza, CSIC, Zaragoza 50009, Spain
| | - Víctor Polo
- Facultad
de Ciencias, Departamento de Química Física, BIFI, Universidad de Zaragoza, Zaragoza 50009, Spain
| | - Francisco J. Fernández-Alvarez
- Facultad
de Ciencias, Departamento de Química Inorgánica, Instituto
de Síntesis Química y Catálisis Homogénea, Universidad de Zaragoza, CSIC, Zaragoza 50009, Spain
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8
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Brodie CN, Sotorrios L, Boyd TM, Macgregor SA, Weller AS. Dehydropolymerization of H 3B·NMeH 2 Mediated by Cationic Iridium(III) Precatalysts Bearing κ 3- iPr-PN RP Pincer Ligands ( R = H, Me): An Unexpected Inner-Sphere Mechanism. ACS Catal 2022; 12:13050-13064. [PMID: 36313521 PMCID: PMC9594342 DOI: 10.1021/acscatal.2c03778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/27/2022] [Indexed: 11/30/2022]
Abstract
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The dehydropolymerization of H3B·NMeH2 to form N-methylpolyaminoborane using neutral
and
cationic catalysts based on the {Ir(iPr-PNHP)} fragment [iPr-PNHP = κ3-(CH2CH2PiPr2)2NH] is reported. Neutral
Ir(iPr-PNHP)H3 or
Ir(iPr-PNHP)H2Cl
precatalysts show no, or poor and unselective, activity respectively
at 298 K in 1,2-F2C6H4 solution.
In contrast, addition of [NMeH3][BArF4] (ArF = 3,5-(CF3)2C6H3) to Ir(iPr-PNHP)H3 immediately starts catalysis, suggesting that a cationic
catalytic manifold operates. Consistent with this, independently synthesized
cationic precatalysts are active (tested between 0.5 and 2.0 mol %
loading) producing poly(N-methylaminoborane) with Mn ∼ 40,000 g/mol, Đ ∼1.5, i.e., dihydrogen/dihydride, [Ir(iPr-PNHP)(H)2(H2)][BArF4]; σ-amine-borane [Ir(iPr-PNHP)(H)2(H3B·NMe3)][BArF4]; and [Ir(iPr-PNHP)(H)2(NMeH2)][BArF4]. Density functional theory (DFT) calculations
probe hydride exchange processes in two of these complexes and also
show that the barrier to amine-borane dehydrogenation is lower (22.5
kcal/mol) for the cationic system compared with the neutral system
(24.3 kcal/mol). The calculations show that the dehydrogenation proceeds
via an inner-sphere process without metal–ligand cooperativity,
and this is supported experimentally by N–Me substituted [Ir(iPr-PNMeP)(H)2(H3B·NMe3)][BArF4] being
an active catalyst. Key to the lower barrier calculated for the cationic
system is the outer-sphere coordination of an additional H3B·NMeH2 with the N–H group of the ligand.
Experimentally, kinetic studies indicate a complex reaction manifold
that shows pronounced deceleratory temporal profiles. As supported
by speciation and DFT studies, a key observation is that deprotonation
of [Ir(iPr-NHP)(H)2(H2)][BArF4], formed upon amine-borane
dehydrogenation, by the slow in situ formation of NMeH2 (via B–N bond cleavage), results in the formation of essentially
inactive Ir(iPr-PNHP)H3, with a coproduct of [NMeH3]+/[H2B(NMeH2)2]+. While reprotonation
of Ir(iPr-PNHP)H3 results in a return to the cationic cycle, it is proposed, supported
by doping experiments, that reprotonation is attenuated by entrainment
of the [NMeH3]+/[H2B(NMeH2)2]+/catalyst in insoluble polyaminoborane.
The role of [NMeH3]+/[H2B(NMeH2)]+ as chain control agents is also noted.
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Affiliation(s)
| | - Lia Sotorrios
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Timothy M. Boyd
- Department of Chemistry, University of York, York YO10 5DD, U.K
- Chemistry Research Laboratories, University of Oxford, Oxford OX1 3TA, U.K
| | - Stuart A. Macgregor
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
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9
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Ríos P, Conejero S, Fernández I. Bonding Situation of σ-E-H Complexes in Transition Metal and Main Group Compounds. Chemistry 2022; 28:e202201920. [PMID: 35900796 PMCID: PMC9804526 DOI: 10.1002/chem.202201920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Indexed: 01/05/2023]
Abstract
The ambiguous bonding situation of σ-E-H (E=Si, B) complexes in transition metal compounds has been rationalized by means of Density Functional Theory calculations. To this end, the combination of the Energy Decomposition Analysis (EDA) method and its Natural Orbital for Chemical Valance (NOCV) extension has been applied to representative complexes described in the literature where the possible η1 versus η2 coordination mode is not unambiguously defined. Our quantitative analyses, which complement previous data based on the application of the Quantum Theory of Atoms in Molecules (QTAIM) approach, indicate that there exists a continuum between genuine η1 and η2 modes depending mainly on the strength of the backdonation. Finally, we also applied this EDA-NOCV approach to related main-group species where the backdonation is minimal.
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Affiliation(s)
- Pablo Ríos
- Instituto de Investigaciones Químicas (IIQ)Departamento de Química InorgánicaCentro de Innovación en Química Avanzada (ORFEO-CINQA)CSIC and Universidad de SevillaAvda. Américo Vespucio 4941092SevillaSpain
| | - Salvador Conejero
- Instituto de Investigaciones Químicas (IIQ)Departamento de Química InorgánicaCentro de Innovación en Química Avanzada (ORFEO-CINQA)CSIC and Universidad de SevillaAvda. Américo Vespucio 4941092SevillaSpain
| | - Israel Fernández
- Departamento de Química OrgánicaCentro de Innovación en Química Avanzada (ORFEO-CINQA)Facultad de Ciencias QuímicasUniversidad Complutense de MadridCuidad Universitaria28040-MadridSpain
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10
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Hamdaoui M, Liu F, Cornaton Y, Lu X, Shi X, Zhang H, Liu J, Spingler B, Djukic JP, Duttwyler S. An Iridium-Stabilized Borenium Intermediate. J Am Chem Soc 2022; 144:18359-18374. [PMID: 36173688 DOI: 10.1021/jacs.2c06298] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Exploration of new organometallic systems based on polyhedral boron clusters has the potential to solve challenging chemical problems such as the stabilization of reactive intermediates and transition-state-like species postulated for E-H (E = H, B, C, Si) bond activation reactions. We report on facile and clean B-H activation of a hydroborane by a new iridium boron cluster complex. The product of this reaction is an unprecedented and fully characterized transition metal-stabilized boron cation or borenium. Moreover, this intermediate bears an unusual intramolecular B···H interaction between the hydrogen originating from the activated hydroborane and the cyclometallated metal-bonded boron atom of the boron cluster. This B···H interaction is proposed to be an arrested insertion of hydrogen into the Bcage-metal bond and the initiation step for iridium "cage-walking" around the upper surface of the boron cluster. The "cage-walking" process is supported by the hydrogen-deuterium exchange observed at the boron cluster, and a mechanism is proposed on the basis of theoretical methods with a special focus on the role of noncovalent interactions. All new compounds were isolated and fully characterized by NMR spectroscopy and elemental analysis. Key compounds were studied by single crystal X-ray diffraction and X-ray photoelectron spectroscopy.
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Affiliation(s)
- Mustapha Hamdaoui
- Department of Chemistry, Zheijang University, Hangzhou 310027, China
| | - Fan Liu
- Department of Chemistry, Zheijang University, Hangzhou 310027, China
| | - Yann Cornaton
- Laboratoire de Chimie et Systémique Organométalliques, Institut de Chimie de Strasbourg UMR 7177 CNRS, Université de Strasbourg, Strasbourg 67000, France
| | - Xingyu Lu
- Instrumentation Service Center for Molecular Sciences, Westlake University, Hangzhou 310024, China
| | - Xiaohuo Shi
- Instrumentation Service Center for Molecular Sciences, Westlake University, Hangzhou 310024, China
| | - Huan Zhang
- Instrumentation Service Center for Molecular Sciences, Westlake University, Hangzhou 310024, China
| | - Jiyong Liu
- Department of Chemistry, Zheijang University, Hangzhou 310027, China
| | - Bernhard Spingler
- Department of Chemistry, University of Zurich, Zurich 8057, Switzerland
| | - Jean-Pierre Djukic
- Laboratoire de Chimie et Systémique Organométalliques, Institut de Chimie de Strasbourg UMR 7177 CNRS, Université de Strasbourg, Strasbourg 67000, France
| | - Simon Duttwyler
- Department of Chemistry, Zheijang University, Hangzhou 310027, China
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11
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Sultana M, Bhattacharjee I, Bhunya S, Paul A. Uncovering the Synchronous Role of Bis‐borane with Nucleophilic Solvent as Frustrated Lewis pair in Metal‐free Catalytic Dehydrogenation of Ammonia‐borane. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Munia Sultana
- Indian Association for the Cultivation of Science School of Chemical Sciences INDIA
| | - Ishita Bhattacharjee
- Indian Association for the Cultivation of Science School of Chemical Sciences INDIA
| | - Sourav Bhunya
- Indian Association for the Cultivation of Science School of Chemical Sciences INDIA
| | - Ankan Paul
- Indian Association for the Cultivation of Science Raman Centre for Atomic, Molecular and Optical Sciences 2A and 2B, Raja S. C. Mullick RoadJadavpur 700032 Kolkata INDIA
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