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Antonio JJ, Kraka E. Metal-ring interactions in group 2 ansa-metallocenes: assessed with the local vibrational mode theory. Phys Chem Chem Phys 2024; 26:15143-15155. [PMID: 38647402 DOI: 10.1039/d4cp00225c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Ansa-metallocenes, a vital class of organometallic compounds, have attracted significant attention due to their diverse structural motifs and their pivotal roles in catalysis and materials science. We investigated 37 distinct group 2 ansa-metallocenes at the B3LYP-D3/def2-TZVP level of theory. Utilizing local mode force constants derived from our local vibrational mode theory, including a special force constant directly targeting the metal-ring interaction, we could unveil latent structural differences between solvated and non-solvated metallocenophanes and the influence of the solvent on complex stability and structure. We could quantify the intrinsic strength of the metal-cyclopentadienyl (M-Cp) bonds and the influence of the bridging motifs on the stiffness of the Cp-M-Cp angles, another determinant of complex stability. LMA was complemented by the analysis of electronic density, utilizing the quantum theory of atoms in molecules (QTAIM), which confirmed both the impact of solvent coordination on the strength of the M-Cp bond(s) and the influence of the bridging motif on the Cp-M-Cp angles. The specific effect of the ansa-motif on the M-Cp interaction was further elucidated by a comparison with linear/bent metallocene structures. In summary, our results identify the local mode analysis as an efficient tool for unraveling the intricate molecular properties of ansa-metallocenes and their unique structural features.
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Affiliation(s)
- Juliana J Antonio
- Computational and Theoretical Chemistry Group (CATCO), Department of Chemistry, Southern Methodist University, 3215 Daniel Ave, Dallas, TX 75275-0314, USA.
| | - Elfi Kraka
- Computational and Theoretical Chemistry Group (CATCO), Department of Chemistry, Southern Methodist University, 3215 Daniel Ave, Dallas, TX 75275-0314, USA.
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2
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Lugo-Fuentes LI, Lucas-Rosales VA, Sandoval-Mendoza JA, Shang R, Martínez JP, Jiménez-Halla JOC. Different Reaction Modes Operating in ansa-Half-Sandwich Magnesium Catalysts. Chemistry 2024; 30:e202304130. [PMID: 38350013 DOI: 10.1002/chem.202304130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/22/2024] [Accepted: 02/13/2024] [Indexed: 02/15/2024]
Abstract
Magnesium-based catalysts are becoming popular for hydroelementation reactions specially using p-block reagents. Based on the seminal report from Schäfer's group (ChemCatChem 2022, 14, e202201007), our study demonstrates that the reaction mechanisms exhibit a far greater degree of complexity than originally presumed. Magnesium has a variety of coordination modes (and access to different hybridizations) which allows this electron-deficient centre to modulate its catalytic power depending on the σ-donor properties of the reagent. DFT calculations demonstrate several reaction channels closely operating in these versatile catalysts. In addition, variations in limiting energy barriers resulting from catalyst modifications were examined as a function of the Hammett constant, thereby predicting enhanced efficiency in reaction conversions.
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Affiliation(s)
- Leonardo I Lugo-Fuentes
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Campus Gto, Noria Alta S/N, CP, 36050, Guanajuato, México
| | - Victor A Lucas-Rosales
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Campus Gto, Noria Alta S/N, CP, 36050, Guanajuato, México
| | - J Antonio Sandoval-Mendoza
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Campus Gto, Noria Alta S/N, CP, 36050, Guanajuato, México
| | - Rong Shang
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8526, Hiroshima, Japan
| | - Juan Pablo Martínez
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097, Warszawa
| | - J Oscar C Jiménez-Halla
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Campus Gto, Noria Alta S/N, CP, 36050, Guanajuato, México
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3
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Sergeieva T, Demirer TI, Wuttke A, Mata RA, Schäfer A, Linker GJ, Andrada DM. Revisiting the origin of the bending in group 2 metallocenes AeCp 2 (Ae = Be-Ba). Phys Chem Chem Phys 2023. [PMID: 37482883 PMCID: PMC10395002 DOI: 10.1039/d2cp05020j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
Metallocenes are well-established compounds in organometallic chemistry, and can exhibit either a coplanar structure or a bent structure according to the nature of the metal center (E) and the cyclopentadienyl ligands (Cp). Herein, we re-examine the chemical bonding to underline the origins of the geometry and stability observed experimentally. To this end, we have analysed a series of group 2 metallocenes [Ae(C5R5)2] (Ae = Be-Ba and R = H, Me, F, Cl, Br, and I) with a combination of computational methods, namely energy decomposition analysis (EDA), polarizability model (PM), and dispersion interaction densities (DIDs). Although the metal-ligand bonding nature is mainly an electrostatic interaction (65-78%), the covalent character is not negligible (33-22%). Notably, the heavier the metal center, the stronger the d-orbital interaction with a 50% contribution to the total covalent interaction. The dispersion interaction between the Cp ligands counts only for 1% of the interaction. Despite that orbital contributions become stronger for heavier metals, they never represent the energy main term. Instead, given the electrostatic nature of the metallocene bonds, we propose a model based on polarizability, which faithfully predicts the bending angle. Although dispersion interactions have a fair contribution to strengthen the bending angle, the polarizability plays a major role.
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Affiliation(s)
- Tetiana Sergeieva
- Department of Chemistry, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Germany.
| | - T Ilgin Demirer
- Department of Chemistry, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Germany.
| | - Axel Wuttke
- Institute for Physical Chemistry, Georg-August-University Göttingen, Tammannstrasse 6, D-37077 Göttingen, Germany.
| | - Ricardo A Mata
- Institute for Physical Chemistry, Georg-August-University Göttingen, Tammannstrasse 6, D-37077 Göttingen, Germany.
| | - André Schäfer
- Department of Chemistry, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Germany.
| | - Gerrit-Jan Linker
- MESA+ Institute for Nanotechnology, University of Twente, 7522 NB Enschede, The Netherlands.
| | - Diego M Andrada
- Department of Chemistry, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Germany.
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Bischoff IA, Seydo Meme R, Bhatti MS, Morgenstern B, Schäfer A. Bis(indenyl)tetrelocenophanes: Introducing ansa-Indenyl Ligand Systems to the p-Block. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Inga-Alexandra Bischoff
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Saarland, Germany
| | - Ronay Seydo Meme
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Saarland, Germany
| | - Muniba Shahzad Bhatti
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Saarland, Germany
| | - Bernd Morgenstern
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Saarland, Germany
| | - André Schäfer
- Department of Chemistry, Faculty of Natural Sciences and Technology, Saarland University, Campus Saarbrücken, 66123 Saarbrücken, Saarland, Germany
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Wirtz L, Ghulam KY, Morgenstern B, Schäfer A. Constrained Geometry
ansa
‐Half‐Sandwich Complexes of Magnesium – Versatile
s
‐Block Catalysts. ChemCatChem 2022. [DOI: 10.1002/cctc.202201007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Lisa Wirtz
- Faculty of Natural Science and Technology Department of Chemistry Saarland University Campus Saarbrücken 66123 Saarbrücken Germany
| | - Kinza Yasmin Ghulam
- Faculty of Natural Science and Technology Department of Chemistry Saarland University Campus Saarbrücken 66123 Saarbrücken Germany
| | - Bernd Morgenstern
- Faculty of Natural Science and Technology Department of Chemistry Saarland University Campus Saarbrücken 66123 Saarbrücken Germany
| | - André Schäfer
- Faculty of Natural Science and Technology Department of Chemistry Saarland University Campus Saarbrücken 66123 Saarbrücken Germany
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Grabowski SJ, Parra RD. Sandwich, Triple-Decker and Other Sandwich-like Complexes of Cyclopentadienyl Anions with Lithium or Sodium Cations. Molecules 2022; 27:molecules27196269. [PMID: 36234808 PMCID: PMC9571536 DOI: 10.3390/molecules27196269] [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: 08/31/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 11/16/2022] Open
Abstract
Density functional theory, DFT, calculations were carried out on complexes containing cyclopentadienyl anions and lithium or sodium cations; half-sandwich, sandwich and sandwich-like complexes (among them triple-decker ones) are analyzed. Searches performed through the Cambridge Structural Database revealed that crystal structures containing these motifs exist, mostly structures with sodium cations. The DFT calculations performed here include geometry optimization and frequency calculations of the complexes at the ωB97XD/aug-cc-pVTZ level, followed by the partitioning of the energy of interaction via the Energy Decomposition Analysis scheme, EDA, at the BP86-D3/TZ2P level. Additional calculations and analyses were performed using both the Quantum Theory of Atoms in Molecules, QTAIM, and the Natural Bond Orbital analyses, NBO. The results of this work show that the electrostatic interaction energy is the most important attractive contribution to the total interaction energy of each of the complex systems analyzed here, and that complexation itself leads to minor electron charge shifts.
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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, Spain
- Ikerbasque, Basque Foundation for Science, 48011 Bilbao, Spain
- Correspondence: (S.J.G.); (R.D.P.)
| | - Rubén D. Parra
- Department of Chemistry and Biochemistry, DePaul University, Chicago, IL 60614, USA
- Correspondence: (S.J.G.); (R.D.P.)
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Baguli S, Mondal S, Mandal C, Goswami S, Mukherjee D. Cyclopentadienyl Complexes of the Alkaline Earths in Light of the Periodic Trends. Chem Asian J 2022; 17:e202100962. [PMID: 34825506 DOI: 10.1002/asia.202100962] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/02/2021] [Indexed: 11/09/2022]
Abstract
The electron-rich cyclopentadienyl and the analogous indenyl and fluorenyl ligands (collectively denoted here as Cp') have been impactful in stabilizing electron-deficient metal centers including the highly electropositive alkaline earths. Being in the s-block, the group 2 metals follow a major periodic variation in their atomic and ionic properties which is reflected in those Cp' compounds. This article presents an overview of this class of compounds for all the five metals from beryllium to barium (radium is excluded for its radioactivity), highlighting their systematic variation.
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Affiliation(s)
- Sudip Baguli
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Nadia, 741246, West Bengal, India
| | - Sumana Mondal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Nadia, 741246, West Bengal, India
| | - Chhotan Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Nadia, 741246, West Bengal, India
| | - Santu Goswami
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Nadia, 741246, West Bengal, India
| | - Debabrata Mukherjee
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Nadia, 741246, West Bengal, India
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Synthesis and structure of an asymmetrical sila[1]magnesocenophane. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2021. [DOI: 10.1515/znb-2021-0152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The synthesis and structure of an asymmetrical sila[1]magnesocenophane, featuring a cyclopentadienyl and a tetramethylcyclopentadienyl group, are reported. The compound was obtained as a bis(tetrahydrofuran) adduct and exhibits a slipped sandwich structure in the solid state.
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10
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Grabowski SJ. The coordination of beryllium and magnesium centres in half-sandwich and sandwich compounds. J Organomet Chem 2021. [DOI: 10.1016/j.jorganchem.2021.121906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Wirtz L, Lambert J, Morgenstern B, Schäfer A. Cross-Dehydrocoupling of Amines and Silanes Catalyzed by Magnesocenophanes. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00245] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Lisa Wirtz
- Saarland University, Faculty of Natural Sciences and Technology, Department of Chemistry, Campus Saarbrücken, 66123 Saarbrücken, Federal Republic of Germany
| | - Jessica Lambert
- Saarland University, Faculty of Natural Sciences and Technology, Department of Chemistry, Campus Saarbrücken, 66123 Saarbrücken, Federal Republic of Germany
| | - Bernd Morgenstern
- Saarland University, Faculty of Natural Sciences and Technology, Department of Chemistry, Campus Saarbrücken, 66123 Saarbrücken, Federal Republic of Germany
| | - André Schäfer
- Saarland University, Faculty of Natural Sciences and Technology, Department of Chemistry, Campus Saarbrücken, 66123 Saarbrücken, Federal Republic of Germany
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12
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Abstract
Metallocenes with interlinked cyclopentadienide ligands are commonly referred to as ansa-metallocenes or metallocenophanes. These can have drastically different properties than their unbridged parent compounds. While this concept is best known for transition metals such as iron, it can also be adopted for many main-group elements. This review aims to summarize recent advances in the field of metallocenophanes based on main-group elements of group 2, group 13, group 14 and group 15, focusing on synthesis, structure and properties of these compounds.
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Affiliation(s)
- Lisa Wirtz
- Faculty of Natural Science and TechnologyDepartment of ChemistrySaarland UniversityCampus Saarbrücken66123SaarbrückenGermany
| | - André Schäfer
- Faculty of Natural Science and TechnologyDepartment of ChemistrySaarland UniversityCampus Saarbrücken66123SaarbrückenGermany
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