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Dankert F, Hevia E. Synthesis and Modular Reactivity of Low Valent Al/Zn Heterobimetallics Supported by Common Monodentate Amides. Chemistry 2024; 30:e202304336. [PMID: 38189633 DOI: 10.1002/chem.202304336] [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: 01/02/2024] [Revised: 01/05/2024] [Accepted: 01/05/2024] [Indexed: 01/09/2024]
Abstract
Recent advances on low valent main group metal chemistry have shown the excellent potential of heterobimetallic complexes derived from Al(I) to promote cooperative small molecule activation processes. A signature feature of these complexes is the use of bulky chelating ligands which act as spectators providing kinetic stabilization to their highly reactive Al-M bonds. Here we report the synthesis of novel Al/Zn bimetallics prepared by the selective formal insertion of AlCp* into the Zn-N bond of the utility zinc amides ZnR2 (R=HMDS, hexamethyldisilazide; or TMP, 2,2,6,6-tetramethylpiperidide). By systematically assessing the reactivity of the new [(R)(Cp*)AlZn(R)] bimetallics towards carbodiimides, structural and mechanistic insights have been gained on their ability to undergo insertion in their Zn-Al bond. Disclosing a ligand effect, when R=TMP, an isomerization process can be induced giving [(TMP)2AlZn(Cp*)] which displays a special reactivity towards carbodiimides and carbon dioxide involving both its Al-N bonds, leaving its Al-Zn bond untouched.
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Affiliation(s)
- Fabian Dankert
- Department für Chemie, Biochemie und Pharmazie, Universität Bern, Freiestraße 3, Bern, 3012, Switzerland
| | - Eva Hevia
- Department für Chemie, Biochemie und Pharmazie, Universität Bern, Freiestraße 3, Bern, 3012, Switzerland
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2
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Ackermann MT, Szlosek R, Riesinger C, Seidl M, Timoshkin AY, Rivard E, Scheer M. NHC-Stabilized Mixed Group 13/14/15 Element Hydrides. Chemistry 2024; 30:e202303680. [PMID: 38009601 DOI: 10.1002/chem.202303680] [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: 11/06/2023] [Revised: 11/25/2023] [Accepted: 11/27/2023] [Indexed: 11/29/2023]
Abstract
The syntheses of novel N-heterocyclic carbene (NHC) adducts of group 13, 14 and 15 element hydrides are reported. Salt metathesis reactions between NaPH2 and IDipp ⋅ GeH2 BH2 OTf (1) (IDipp=1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) led to mixtures of the two isomers IDipp ⋅ GeH2 BH2 PH2 (2 a) and IDipp ⋅ BH2 GeH2 PH2 (2 b); by altering the reaction conditions an almost exclusive formation of 2 b was achieved. Attempts to purify mixtures of 2 a and 2 b by re-crystallization from THF afforded a salt [IDipp ⋅ GeH2 BH2 ⋅ IDipp][PHGeH2 BH2 PH2 BH2 GeH2 ] (4) that contains the novel anionic cyclohexyl-like inorganic heterocycle [PHGeH2 BH2 PH2 BH2 GeH2 ]- . In addition, the borane adducts IDipp ⋅ GeH2 BH2 PH2 BH3 (3 a) and IDipp ⋅ BH2 GeH2 PH2 BH3 (3 b) as even longer chain compounds were obtained from reactions of 2 a/2 b with H3 B ⋅ SMe2 and were studied by NMR spectroscopy. Accompanying DFT computations give insight into the mechanism and energetics associated with 2 a/2 b isomerization as well as their decomposition pathways.
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Affiliation(s)
- Matthias T Ackermann
- Institute of Inorganic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Robert Szlosek
- Institute of Inorganic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Christoph Riesinger
- Institute of Inorganic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Michael Seidl
- Institute of General and Theoretical Chemistry, University of Innsbruck, Innrain 80-82, 6020, Innsbruck, Austria
| | - Alexey Y Timoshkin
- Institute of Chemistry, Saint Petersburg State University, Universitetskaya emb. 7/9, 199034, St Petersburg, Russia
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr, Edmonton, Alberta, T6G 2G2, Canada
| | - Manfred Scheer
- Institute of Inorganic Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
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3
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Mandal D, Demirer TI, Sergeieva T, Morgenstern B, Wiedemann HTA, Kay CWM, Andrada DM. Evidence of Al II Radical Addition to Benzene. Angew Chem Int Ed Engl 2023; 62:e202217184. [PMID: 36594569 DOI: 10.1002/anie.202217184] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 12/23/2022] [Accepted: 01/03/2023] [Indexed: 01/04/2023]
Abstract
Electrophilic AlIII species have long dominated the aluminum reactivity towards arenes. Recently, nucleophilic low-valent AlI aluminyl anions have showcased oxidative additions towards arenes C-C and/or C-H bonds. Herein, we communicate compelling evidence of an AlII radical addition reaction to the benzene ring. The electron reduction of a ligand stabilized precursor with KC8 in benzene furnishes a double addition to the benzene ring instead of a C-H bond activation, producing the corresponding cyclohexa-1,3(orl,4)-dienes as Birch-type reduction product. X-ray crystallographic analysis, EPR spectroscopy, and DFT results suggest this reactivity proceeds through a stable AlII radical intermediate, whose stability is a consequence of a rigid scaffold in combination with strong steric protection.
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Affiliation(s)
- Debdeep Mandal
- General and Inorganic Chemistry Department, University of Saarland, Campus C4.1, 66123, Saarbrücken, Germany
| | - T Ilgin Demirer
- General and Inorganic Chemistry Department, University of Saarland, Campus C4.1, 66123, Saarbrücken, Germany
| | - Tetiana Sergeieva
- General and Inorganic Chemistry Department, University of Saarland, Campus C4.1, 66123, Saarbrücken, Germany
| | - Bernd Morgenstern
- General and Inorganic Chemistry Department, University of Saarland, Campus C4.1, 66123, Saarbrücken, Germany
| | - Haakon T A Wiedemann
- Physical Chemistry Department, University of Saarland, Campus B2.2, 66123, Saarbrücken, Germany
| | - Christopher W M Kay
- Physical Chemistry Department, University of Saarland, Campus B2.2, 66123, Saarbrücken, Germany.,London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK
| | - Diego M Andrada
- General and Inorganic Chemistry Department, University of Saarland, Campus C4.1, 66123, Saarbrücken, Germany
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4
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Xu F, Zhu J. Probing a General Strategy to Break the C-C Bond of Benzene by a Cyclic (Alkyl)(Amino)Aluminyl Anion. Chemistry 2023; 29:e202203216. [PMID: 36349746 DOI: 10.1002/chem.202203216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/08/2022] [Accepted: 11/09/2022] [Indexed: 11/10/2022]
Abstract
The oxidative addition of C-C bonds in aromatic hydrocarbons by low valent main group species has attracted considerable attention from both theoretical and experimental chemists due to the big challenge in breaking their aromaticity. Herein, a general strategy to break the C-C bonds in benzene by cyclic (alkyl)(amino)aluminyl anion is demonstrated via density functional theory (DFT) calculations. The results suggest that the activation of the C-C bond of benzene by this anion is both kinetically and thermodynamically unfavorable whereas introducing electron-withdrawing groups makes such C-C bond activation becomes favorable both kinetically and thermodynamically. Such a sharp change on the kinetics and thermodynamics could be rationalized by the frontier molecular orbital theory by decreasing the lowest unoccupied molecular orbitals of the mono- and disubstituted benzenes. Aromaticity is found to stabilize the transition state for the ring open step. All these findings can help develop the chemistry of small-molecule activation.
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Affiliation(s)
- Fangzhou Xu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Department of Chemistry College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Jun Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Department of Chemistry College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
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5
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Villegas-Escobar N, Hoobler PR, Toro-Labbé A, Schaefer HF. High-Level Coupled-Cluster Study on Substituent Effects in H 2 Activation by Low-Valent Aluminyl Anions. J Phys Chem A 2023; 127:956-965. [PMID: 36689320 DOI: 10.1021/acs.jpca.2c08403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The synthesis of novel aluminyl anion complexes has been well exploited in recent years. Moreover, the elucidation of the structure and reactivity of these complexes opens the path toward a new understanding of low-valent aluminum complexes and their chemistry. This work computationally treats the substituent effect on aluminyl anions to discover suitable alternatives for H2 activation at a high level of theory utilizing coupled-cluster techniques extrapolated to the complete basis set. The results reveal that the simplest AlH2- system is the most reactive toward the activation of H2, but due to the low steric demand, severe difficulty in the stabilization of this system makes its use nonviable. However, the results indicate that, in principle, aluminyl systems with -C, -CN, -NC, and -N chelating centers would be the best choices of ligand toward the activation of molecular hydrogen by taking care of suitable steric demand to prevent dimerization of the catalysts. Furthermore, computations show that monosubstitution (besides -H) in aluminyl anions is preferred over disubstitution. So our predictions show that bidentate ligands may yield less reactive aluminyl anions to activate H2 than monodentate ones.
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Affiliation(s)
- Nery Villegas-Escobar
- Departamento de Físico-Química, Facultad de Ciencias Químicas, Universidad de Concepción, Concepción4070386, Chile
| | - Preston R Hoobler
- Department of Chemistry, Covenant College, Lookout Mountain, Georgia30750, United States
| | - Alejandro Toro-Labbé
- Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna, 4860Santiago, Chile
| | - Henry F Schaefer
- Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia30602, United States
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Heilmann A, Vasko P, Hicks J, Goicoechea JM, Aldridge S. An Aluminium Imide as a Transfer Agent for the [NR] 2- Function via Metathesis Chemistry. Chemistry 2023; 29:e202300018. [PMID: 36602941 DOI: 10.1002/chem.202300018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 01/05/2023] [Accepted: 01/05/2023] [Indexed: 01/06/2023]
Abstract
The reactions of a terminal aluminium imide with a range of oxygen-containing substrates have been probed with a view to developing its use as a novel main group transfer agent for the [NR]2- fragment. We demonstrate transfer of the imide moiety to [N2 ], [CO] and [Ph(H)C] units driven thermodynamically by Al-O bond formation. N2 O reacts rapidly to generate the organoazide DippN3 (Dipp=2,6-i Pr2 C6 H3 ), while CO2 (under dilute reaction conditions) yields the corresponding isocyanate, DippNCO. Mechanistic studies, using both experimental and quantum chemical techniques, identify a carbamate complex K2 [(NON)Al-{κ2 -(N,O)-N(Dipp)CO2 }]2 (formed via [2+2] cycloaddition) as an intermediate in the formation of DippNCO, and also in an alternative reaction leading to the generation of the amino-dicarboxylate complex K2 [(NON)Al{κ2 -(O,O')-(O2 C)2 N-(Dipp)}] (via the take-up of a second equivalent of CO2 ). In the case of benzaldehyde, a similar [2+2] cycloaddition process generates the metallacyclic hemi-aminal complex, Kn [(NON)Al{κ2 -(N,O)-(N(Dipp)C(Ph)(H)O}]n . Extrusion of the imine, PhC(H)NDipp, via cyclo-reversion is disfavoured thermally, due to the high energy of the putative aluminium oxide co-product, K2 [(NON)Al(O)]2 . However, addition of CO2 allows the imine to be released, driven by the formation of the thermodynamically more stable aluminium carbonate co-product, K2 [(NON)Al(κ2 -(O,O')-CO3 )]2 .
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Affiliation(s)
- Andreas Heilmann
- Inorganic Chemistry Laboratory Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Petra Vasko
- Department of Chemistry, University of Helsinki, A. I. Virtasen Aukio 1, PO Box 55, 00014, Helsinki, Finland
| | - Jamie Hicks
- Inorganic Chemistry Laboratory Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Jose M Goicoechea
- Inorganic Chemistry Laboratory Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
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Yan C, Kinjo R. A Three‐Membered Diazo‐Aluminum Heterocycle to Access an Al=C π Bonding Species. Angew Chem Int Ed Engl 2022; 61:e202211800. [DOI: 10.1002/anie.202211800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Chenting Yan
- School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Singapore 637371 Singapore
| | - Rei Kinjo
- School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Singapore 637371 Singapore
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8
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Zhang X, Mei Y, Liu LL. Free Aluminylenes: An Emerging Class of Compounds. Chemistry 2022; 28:e202202102. [DOI: 10.1002/chem.202202102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Xin Zhang
- Department of Chemistry Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology Shenzhen 518055 China
| | - Yanbo Mei
- Department of Chemistry Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology Shenzhen 518055 China
| | - Liu Leo Liu
- Department of Chemistry Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology Shenzhen 518055 China
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9
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Yan C, Kinjo R. A Three‐membered Diazo‐Aluminum Heterocycle to Access an Al=C π Bonding Species. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202211800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Chenting Yan
- Nanyang Technological University School of Chemistry, Chemical Engineering and Biotechnology SINGAPORE
| | - Rei Kinjo
- Nanyang Technological University Division of Chemistry and Biological Chemistry 21 Nanyang Link 637371 Singapore SINGAPORE
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10
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Hill MS, Mahon MF, Neale SE, Pearce KG, Schwamm RJ, McMullin C. White Phosphorus Reduction and Oligomerization by a Potassium Diamidoalumanyl. Z Anorg Allg Chem 2022. [DOI: 10.1002/zaac.202200224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Michael Stephen Hill
- University of Bath Chemistry Department of ChemistryUniversity of BathClaverton Down BA2 7AY Bath UNITED KINGDOM
| | - Mary F. Mahon
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK UNITED KINGDOM
| | - Samuel E. Neale
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK UNITED KINGDOM
| | - Kyle G. Pearce
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK UNITED KINGDOM
| | - Ryan J. Schwamm
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK UNITED KINGDOM
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11
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Sorbelli D, Belpassi L, Belanzoni P. Unraveling differences in aluminyl and carbene coordination chemistry: bonding in gold complexes and reactivity with carbon dioxide. Chem Sci 2022; 13:4623-4634. [PMID: 35656139 PMCID: PMC9020189 DOI: 10.1039/d2sc00630h] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/31/2022] [Indexed: 11/21/2022] Open
Abstract
The electronic properties of aluminyl anions have been reported to be strictly related to those of carbenes, which are well-known to be easily tunable via selected structural modifications imposed on their backbone. Since peculiar reactivity of gold-aluminyl complexes towards carbon dioxide has been reported, leading to insertion of CO2 into the Au-Al bond, in this work the electronic structure and reactivity of Au-Al complexes with different aluminyl scaffolds have been systematically studied and compared to carbene analogues. The analyses reveal that, instead, aluminyls and carbenes display a very different behavior when bound to gold, with the aluminyls forming an electron-sharing and weakly polarized Au-Al bond, which turns out to be poorly modulated by structural modifications of the ligand. The reactivity of gold-aluminyl complexes towards CO2 shows, both qualitatively and quantitatively, similar reaction mechanisms, reflecting the scarce tunability of their electronic structure and bond nature. This work provides further insights and perspectives on the properties of the aluminyl anions and their behavior as coordination ligands.
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Affiliation(s)
- Diego Sorbelli
- Department of Chemistry, Biology and Biotechnology, University of Perugia Via Elce di Sotto, 8 - 06123 Perugia Italy
- CNR Institute of Chemical Science and Technologies "Giulio Natta" (CNR-SCITEC) Via Elce di Sotto, 8 - 06123 Perugia Italy
| | - Leonardo Belpassi
- CNR Institute of Chemical Science and Technologies "Giulio Natta" (CNR-SCITEC) Via Elce di Sotto, 8 - 06123 Perugia Italy
| | - Paola Belanzoni
- Department of Chemistry, Biology and Biotechnology, University of Perugia Via Elce di Sotto, 8 - 06123 Perugia Italy
- CNR Institute of Chemical Science and Technologies "Giulio Natta" (CNR-SCITEC) Via Elce di Sotto, 8 - 06123 Perugia Italy
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12
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Evans MJ, Neale SE, Anker MD, McMullin CL, Coles MP. Potassium Aluminyl Promoted Carbonylation of Ethene. Angew Chem Int Ed Engl 2022; 61:e202117396. [PMID: 35166007 PMCID: PMC9307019 DOI: 10.1002/anie.202117396] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Indexed: 01/07/2023]
Abstract
The potassium aluminyl [K{Al(NONDipp)}]2 ([NONDipp]2−=[O{SiMe2NDipp}2]2−, Dipp=2,6‐iPr2C6H3) activates ethene towards carbonylation with CO under mild conditions. An isolated bis‐aluminacyclopropane compound reacted with CO via carbonylation of an Al−C bond, followed by an intramolecular hydrogen shift to form K2[Al(NONDipp)(μ‐CH2CH=CO‐1κ2C1,3‐2κO)Al(NONDipp)Et]. Restricting the chemistry to a mono‐aluminium system allowed isolation of [Al(NONDipp)(CH2CH2CO‐κ2C1,3)]−, which undergoes thermal isomerisation to form the [Al(NONDipp)(CH2CH=CHO‐κ2C,O)]− anion. DFT calculations highlight the stabilising influence of incorporated benzene at multiple steps in the reaction pathways.
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Affiliation(s)
- Matthew J. Evans
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
| | | | - Mathew D. Anker
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
| | | | - Martyn P. Coles
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
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13
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Rae A, Byrne KM, Brown SA, Kennedy AR, Krämer T, Mulvey RE, Robertson SD. Sigma/pi Bonding Preferences of Solvated Alkali-Metal Cations to Ditopic Arylmethyl Anions. Chemistry 2022; 28:e202104260. [PMID: 35170823 PMCID: PMC9310864 DOI: 10.1002/chem.202104260] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Indexed: 12/14/2022]
Abstract
Arylmethyl anions allow alkali‐metals to bind in a σ‐fashion to the lateral carbanionic centre or a π‐fashion to the aryl ring or in between these extremities, with the trend towards π bonding increasing on descending group 1. Here we review known alkali metal structures of diphenylmethane, fluorene, 2‐benzylpyridine and 4‐benzylpyridine. Next, we synthesise Li, Na, K monomers of these diarylmethyls using polydentate donors PMDETA or Me6TREN to remove competing oligomerizing interactions, studying the effect that two aromatic rings has on negative charge (de)localisation via NMR, X‐ray crystallographic and DFT studies. Diphenylmethyl and fluorenyl anions maintain C(H)−M interactions regardless of alkali‐metal, although the adjacent arene carbons engage in interactions with larger alkali‐metals. Introducing a nitrogen atom into the ring (at the 2‐ or 4‐position) encourages relocalisation of negative charge away from the deprotonated carbon and onto nitrogen. Phenyl(2‐pyridyl)methyl moves from an enamide formation at one extremity (lithium) to an aza‐allyl formation at the other extremity (potassium), while C‐ or N‐coordination modes become energetically viable for Na and K phenyl(4‐pyridyl)methyl complexes.
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Affiliation(s)
- Annabel Rae
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK
| | - Keelan M Byrne
- Department of Chemistry, Maynooth University, W23 F2H6, Maynooth, Co Kildare, Ireland
| | - Scott A Brown
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK
| | - Alan R Kennedy
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK
| | - Tobias Krämer
- Department of Chemistry, Maynooth University, W23 F2H6, Maynooth, Co Kildare, Ireland.,Hamilton Institute, Maynooth University, W23 A3HY, Maynooth, Co Kildare, Ireland
| | - Robert E Mulvey
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK
| | - Stuart D Robertson
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK
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14
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Zhang X, Liu LL. Modulating the Frontier Orbitals of an Aluminylene for Facile Dearomatization of Inert Arenes**. Angew Chem Int Ed Engl 2022; 61:e202116658. [DOI: 10.1002/anie.202116658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Indexed: 12/16/2022]
Affiliation(s)
- Xin Zhang
- Department of Chemistry and Shenzhen Grubbs Institute Southern University of Science and Technology Shenzhen 518055 China
| | - Liu Leo Liu
- Department of Chemistry and Shenzhen Grubbs Institute Southern University of Science and Technology Shenzhen 518055 China
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15
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Evans MJ, Neale SE, Anker MD, McMullin CL, Coles MP. Potassium Aluminyl Promoted Carbonylation of Ethene. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202117396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Matthew J. Evans
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
| | | | - Mathew D. Anker
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
| | | | - Martyn P. Coles
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
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16
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Zhang X, Liu LL. Modulating the Frontier Orbitals of an Aluminylene for Facile Dearomatization of Inert Arenes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202116658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Xin Zhang
- SUSTech: Southern University of Science and Technology Chemistry CHINA
| | - Liu Leo Liu
- Southern University of Science and Technology Chemistry 1088 Xueyuandadao 518055 Shenzhen CHINA
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17
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Zhang X, Liu LL. A Free Aluminylene with Diverse σ‐Donating and Doubly σ/π‐Accepting Ligand Features for Transition Metals**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Xin Zhang
- Department of Chemistry and Shenzhen Grubbs Institute Southern University of Science and Technology Shenzhen 518055 China
| | - Liu Leo Liu
- Department of Chemistry and Shenzhen Grubbs Institute Southern University of Science and Technology Shenzhen 518055 China
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18
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Zhang X, Liu LL. A Free Aluminylene with Diverse σ-Donating and Doubly σ/π-Accepting Ligand Features for Transition Metals*. Angew Chem Int Ed Engl 2021; 60:27062-27069. [PMID: 34614275 DOI: 10.1002/anie.202111975] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/26/2021] [Indexed: 12/15/2022]
Abstract
We report herein the synthesis, characterization, and coordination chemistry of a free N-aluminylene, namely a carbazolylaluminylene 2 b. This species is prepared via a reduction reaction of the corresponding carbazolyl aluminium diiodide. The coordination behavior of 2 b towards transition metal centers (W, Cr) is shown to afford a series of novel aluminylene complexes 3-6 with diverse coordination modes. We demonstrate that the tri-active ambiphilic Al center in 2 b can behave as: 1. a σ-donating and doubly π-accepting ligand; 2. a σ-donating, σ-accepting and π-accepting ligand; and 3. a σ-donating and doubly σ-accepting ligand. Additionally, we show ligand exchange at the aluminylene center providing access to the modulation of electronic properties of transition metals without changing the coordinated atoms. Investigations of 2 b with IDippCuCl (IDipp=1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) show an unprecedented aluminylene-alumanyl transformation leading to a rare terminal Cu-alumanyl complex 8. The electronic structures of such complexes and the mechanism of the aluminylene-alumanyl transformation are investigated through density functional theory (DFT) calculations.
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Affiliation(s)
- Xin Zhang
- Department of Chemistry and Shenzhen Grubbs Institute, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Liu Leo Liu
- Department of Chemistry and Shenzhen Grubbs Institute, Southern University of Science and Technology, Shenzhen, 518055, China
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19
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Roy MMD, Heilmann A, Ellwanger MA, Aldridge S. Generation of a π-Bonded Isomer of [P 4 ] 4- by Aluminyl Reduction of White Phosphorus and its Ammonolysis to PH 3. Angew Chem Int Ed Engl 2021; 60:26550-26554. [PMID: 34677901 DOI: 10.1002/anie.202112515] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/20/2021] [Indexed: 11/12/2022]
Abstract
By employing the highly reducing aluminyl complex [K{(NON)Al}]2 (NON=4,5-bis(2,6-diisopropylanilido)-2,7-di-tert-butyl-9,9-dimethylxanthene), we demonstrate the controlled formation of P4 2- and P4 4- complexes from white phosphorus, and chemically reversible inter-conversion between them. The tetra-anion features a unique planar π-bonded structure, with the incorporation of the K+ cations implicit in the use of the anionic nucleophile offering additional stabilization of the unsaturated isomer of the P4 4- fragment. This complex is extremely reactive, acting as a source of P3- : exposure to ammonia leads to the release of phosphine (PH3 ) under mild conditions (room temperature and pressure), which contrast with those necessitated for the direct combination of P4 and NH3 (>5 kbar and >250 °C).
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Affiliation(s)
- Matthew M D Roy
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Andreas Heilmann
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Mathias A Ellwanger
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
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20
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Hoobler PR, Villegas-Escobar N, Turney JM, Toro-Labbé A, Schaefer HF. Substituent Effects on Aluminyl Anions and Derived Systems: A High-Level Theory. J Phys Chem A 2021; 125:10379-10391. [PMID: 34812036 DOI: 10.1021/acs.jpca.1c08918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Aluminyl anions are low-valent aluminum species bearing a lone pair of electrons and a negative charge. These systems have drawn recent synthetic interest for their nucleophilic nature, allowing for the activation of σ-bonds, and have been proposed as a pathway to hydrogen energy storage. In this research, we provide high-level ab initio geometries and energies for both the simplest aluminyl anion (AlH2-) and several substituted derivatives. Geometries are reported using the gold-standard CCSD(T)/aug-cc-pV(T+d)Z level of theory. Energies were extrapolated to the complete basis set limit through the focal point approach, utilizing coupled-cluster methods through perturbative quadruples and basis sets up to five-ζ quality. Geometries were rationalized using electrostatic, steric, and orbital donation effects. The donation from substituents to Al is accompanied by back-donation effects, a property traditionally thought of in transition-metal systems. Stereoelectronic effects through the secondary orbital interaction play a fundamental role in stabilizing these low-valent aluminum compounds and would likely also affect the feasibility of their use within several industrial applications. The energetic analysis of the formation of each substituted anion is rationalized as the result of three energetic schemes. The effectiveness of these schemes for determining the relative formation energies is discussed.
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Affiliation(s)
- Preston R Hoobler
- Department of Chemistry, Covenant College, Lookout Mountain, Georgia 30750, United States
| | - Nery Villegas-Escobar
- Centro Integrativo de Biología y Química Aplicada (CIBQA), Universidad Bernardo O'Higgins, Santiago 8370854, Chile
| | - Justin M Turney
- Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Alejandro Toro-Labbé
- Laboratorio de Química Teórica Computacional (QTC), Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna, Santiago 4860, Chile
| | - Henry F Schaefer
- Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, United States
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21
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Roy MMD, Heilmann A, Ellwanger MA, Aldridge S. Generation of a π‐Bonded Isomer of [P
4
]
4−
by Aluminyl Reduction of White Phosphorus and its Ammonolysis to PH
3. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202112515] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Matthew M. D. Roy
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Andreas Heilmann
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Mathias A. Ellwanger
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
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22
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Schwamm RJ, Hill MS, Liu HY, Mahon MF, McMullin CL, Rajabi NA. Seven-Membered Cyclic Potassium Diamidoalumanyls. Chemistry 2021; 27:14971-14980. [PMID: 34403562 PMCID: PMC8596455 DOI: 10.1002/chem.202102682] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Indexed: 11/08/2022]
Abstract
The seven-membered cyclic potassium alumanyl species, [{SiNMes }AlK]2 [{SiNMes }={CH2 SiMe2 N(Mes)}2 ; Mes=2,4,6-Me3 C6 H2 ], which adopts a dimeric structure supported by flanking K-aryl interactions, has been isolated either by direct reduction of the iodide precursor, [{SiNMes }AlI], or in a stepwise manner via the intermediate dialumane, [{SiNMes }Al]2 . Although the intermediate dialumane has not been observed by reduction of a Dipp-substituted analogue (Dipp=2,6-i-Pr2 C6 H3 ), partial oxidation of the potassium alumanyl species, [{SiNDipp }AlK]2 , where {SiNDipp }={CH2 SiMe2 N(Dipp)}2 , provided the extremely encumbered dialumane [{SiNDipp }Al]2 . [{SiNDipp }AlK]2 reacts with toluene by reductive activation of a methyl C(sp3 )-H bond to provide the benzyl hydridoaluminate, [{SiNDipp }AlH(CH2 Ph)]K, and as a nucleophile with BPh3 and RN=C=NR (R=i-Pr, Cy) to yield the respective Al-B- and Al-C-bonded potassium aluminaborate and alumina-amidinate products. The dimeric structure of [{SiNDipp }AlK]2 can be disrupted by partial or complete sequestration of potassium. Equimolar reactions with 18-crown-6 result in the corresponding monomeric potassium alumanyl, [{SiNDipp }Al-K(18-cr-6)], which provides a rare example of a direct Al-K contact. In contrast, complete encapsulation of the potassium cation of [{SiNDipp }AlK]2 , either by an excess of 18-cr-6 or 2,2,2-cryptand, allows the respective isolation of bright orange charge-separated species comprising the 'free' [{SiNDipp }Al]- alumanyl anion. Density functional theory (DFT) calculations performed on this moiety indicate HOMO-LUMO energy gaps in the of order 200-250 kJ mol-1 .
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Affiliation(s)
- Ryan J Schwamm
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Michael S Hill
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Han-Ying Liu
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Mary F Mahon
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Claire L McMullin
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
| | - Nasir A Rajabi
- Department of Chemistry, University of Bath Claverton Down, Bath, BA2 7AY, UK
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23
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Gendy C, Mikko Rautiainen J, Mailman A, Tuononen HM. Low-Valent Germanylidene Anions: Efficient Single-Site Nucleophiles for Activation of Small Molecules. Chemistry 2021; 27:14405-14409. [PMID: 34403540 PMCID: PMC8596740 DOI: 10.1002/chem.202102804] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Indexed: 11/09/2022]
Abstract
Rare mononuclear and helical chain low-valent germanylidene anions supported by cyclic (alkyl)(amino)carbene and hypermetallyl ligands were synthesised by stepwise reduction from corresponding germylene precursors via stable and isolable germanium radicals. The electronic structures of the anions can be described with ylidene and ylidone resonance forms with the Ge-C π-electrons capable of binding even weak electrophiles. The germanylidene anions reacted with CO2 to give μ-CO2 -κC:κO complexes, a rare coordination mode for low-valent germanium and inaccessible for the related neutral germylones. These results implicate low-valent germanylidene anions as efficient single-site nucleophiles for activation of small molecules.
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Affiliation(s)
- Chris Gendy
- Department of ChemistryNanoScience CentreUniversity of JyväskyläP.O. Box. 3540014JyväskyläFinland
| | - J. Mikko Rautiainen
- Department of ChemistryNanoScience CentreUniversity of JyväskyläP.O. Box. 3540014JyväskyläFinland
| | - Aaron Mailman
- Department of ChemistryNanoScience CentreUniversity of JyväskyläP.O. Box. 3540014JyväskyläFinland
| | - Heikki M. Tuononen
- Department of ChemistryNanoScience CentreUniversity of JyväskyläP.O. Box. 3540014JyväskyläFinland
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24
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Villegas-Escobar N, Toro-Labbé A, Schaefer HF. Contrasting the Mechanism of H 2 Activation by Monomeric and Potassium-Stabilized Dimeric Al I Complexes: Do Potassium Atoms Exert any Cooperative Effect? Chemistry 2021; 27:17369-17378. [PMID: 34613646 DOI: 10.1002/chem.202103082] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Indexed: 11/06/2022]
Abstract
Aluminyl anions are low-valent, anionic, and carbenoid aluminum species commonly found stabilized with potassium cations from the reaction of Al-halogen precursors and alkali compounds. These systems are very reactive toward the activation of σ-bonds and in reactions with electrophiles. Various research groups have detected that the potassium atoms play a stabilization role via electrostatic and cation ⋯ π interactions with nearby (aromatic)-carbocyclic rings from both the ligand and from the reaction with unsaturated substrates. Since stabilizing K⋯H bonds are witnessed in the activation of this class of molecules, we aim to unveil the role of these metals in the activation of the smaller and less polarizable H2 molecule, together with a comprehensive characterization of the reaction mechanism. In this work, the activation of H2 utilizing a NON-xanthene-Al dimer, [K{Al(NON)}]2 (D) and monomeric, [Al(NON)]- (M) complexes are studied using density functional theory and high-level coupled-cluster theory to reveal the potential role of K+ atoms during the activation of this gas. Furthermore, we aim to reveal whether D is more reactive than M (or vice versa), or if complicity between the two monomer units exits within the D complex toward the activation of H2 . The results suggest that activation energies using the dimeric and monomeric complexes were found to be very close (around 33 kcal mol-1 ). However, a partition of activation energies unveiled that the nature of the energy barriers for the monomeric and dimeric complexes are inherently different. The former is dominated by a more substantial distortion of the reactants (and increased interaction energies between them). Interestingly, during the oxidative addition, the distortion of the Al complex is minimal, while H2 distorts the most, usually over 0.77 Δ E d i s t ≠ . Overall, it is found here that electrostatic and induction energies between the complexes and H2 are the main stabilizing components up to the respective transition states. The results suggest that the K+ atoms act as stabilizers of the dimeric structure, and their cooperative role on the reaction mechanism may be negligible, acting as mere spectators in the activation of H2 . Cooperation between the two monomers in D is lacking, and therefore the subsequent activation of H2 is wholly disengaged.
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Affiliation(s)
- Nery Villegas-Escobar
- Centro Integrativo de Biología y Química Aplicada (CIBQA), Universidad Bernardo O'Higgins, General Gana 1702, Santiago, 8370854, Chile
| | - Alejandro Toro-Labbé
- Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago, Chile
| | - Henry F Schaefer
- Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia, 30602, USA
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25
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Evans MJ, Anker MD, McMullin CL, Neale SE, Coles MP. Dihydrogen Activation by Lithium‐ and Sodium‐Aluminyls. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108934] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Matthew J. Evans
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
| | - Mathew D. Anker
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
| | | | - Sam E. Neale
- Department of Chemistry University of Bath Bath BA2 7AY UK
| | - Martyn P. Coles
- School of Chemical and Physical Sciences Victoria University of Wellington PO Box 600 Wellington 6012 New Zealand
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26
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Roy MMD, Hicks J, Vasko P, Heilmann A, Baston A, Goicoechea JM, Aldridge S. Probing the Extremes of Covalency in M−Al bonds: Lithium and Zinc Aluminyl Compounds. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202109416] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Matthew M. D. Roy
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Jamie Hicks
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Petra Vasko
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
- Department of Chemistry, Nanoscience Center University of Jyväskylä P.O. Box 35 Jyväskylä FI-40014 Finland
| | - Andreas Heilmann
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Anne‐Marie Baston
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Jose M. Goicoechea
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
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27
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Cabrera‐Trujillo JJ, Fernández I. Factors Controlling the Aluminum(I)-meta-Selective C-H Activation in Arenes. Chemistry 2021; 27:12422-12429. [PMID: 34184800 PMCID: PMC8457071 DOI: 10.1002/chem.202101944] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Indexed: 11/17/2022]
Abstract
The so far poorly understood factors controlling the complete meta-selectivity observed in the C-H activation reactions of alkylarenes promoted by aluminyl anions have been explored in detail by means of Density Functional Theory calculations. To this end, a combination of state-of-the-art computational methods, namely the activation strain model of reactivity and energy decomposition analysis, has been applied to quantitatively unveil the origin of the selectivity of the transformation as well as the influence of the associated potassium cation. It is found that the selectivity takes place during the initial nucleophilic addition step where the key LP(Al)→π*(C=C) molecular orbital interaction is more stabilizing for the meta-pathway, which results in a stronger interaction between the reactants along the entire transformation.
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Affiliation(s)
- Jorge Juan Cabrera‐Trujillo
- Departmento de Química Orgánica I and Centro de Innovación enQuímica Avanzada (ORFEO-CINQA)Facultad de Ciencias QuímicasUniversidad Complutense de Madrid28040MadridSpain
| | - Israel Fernández
- Departmento de Química Orgánica I and Centro de Innovación enQuímica Avanzada (ORFEO-CINQA)Facultad de Ciencias QuímicasUniversidad Complutense de Madrid28040MadridSpain
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28
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Evans MJ, Anker MD, McMullin CL, Neale SE, Coles MP. Dihydrogen Activation by Lithium- and Sodium-Aluminyls. Angew Chem Int Ed Engl 2021; 60:22289-22292. [PMID: 34402149 DOI: 10.1002/anie.202108934] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Indexed: 01/25/2023]
Abstract
To date, aluminyl anions have been exclusively isolated as their potassium salts. We report herein the synthesis of the lithium and sodium aluminyls, M2 [Al(NONDipp )]2 (M=Li, Na. NONDipp =[O(SiMe2 NDipp)2 ]2- ; Dipp=2,6-iPr2 C6 H3 ). Both compounds crystallize from non-coordinating solvent as "slipped" contacted dimeric pairs with strong M⋅⋅⋅π(aryl) interactions. Isolation from Et2 O solution affords the monomeric ion pairs (NONDipp )Al-M(Et2 O)2 , which contain discrete Al-Li and Al-Na bonds. The ability of the full series of Li, Na and K aluminyls to activate dihydrogen is reported.
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Affiliation(s)
- Matthew J Evans
- School of Chemical and Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6012, New Zealand
| | - Mathew D Anker
- School of Chemical and Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6012, New Zealand
| | | | - Sam E Neale
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Martyn P Coles
- School of Chemical and Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6012, New Zealand
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29
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Roy MMD, Hicks J, Vasko P, Heilmann A, Baston AM, Goicoechea JM, Aldridge S. Probing the Extremes of Covalency in M-Al bonds: Lithium and Zinc Aluminyl Compounds. Angew Chem Int Ed Engl 2021; 60:22301-22306. [PMID: 34396660 DOI: 10.1002/anie.202109416] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/10/2021] [Indexed: 11/08/2022]
Abstract
Synthetic routes to lithium, magnesium, and zinc aluminyl complexes are reported, allowing for the first structural characterization of an unsupported lithium-aluminium bond. Crystallographic and quantum-chemical studies are consistent with the presence of a highly polar Li-Al interaction, characterized by a low bond order and relatively little charge transfer from Al to Li. Comparison with magnesium and zinc aluminyl systems reveals changes to both the M-Al bond and the (NON)Al fragment (where NON=4,5-bis(2,6-diisopropylanilido)-2,7-di-tert-butyl-9,9-dimethylxanthene), consistent with a more covalent character, with the latter complex being shown to react with CO2 via a pathway that implies that the zinc centre acts as the nucleophilic partner.
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Affiliation(s)
- Matthew M D Roy
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Jamie Hicks
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Petra Vasko
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK.,Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, Jyväskylä, FI-40014, Finland
| | - Andreas Heilmann
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Anne-Marie Baston
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Jose M Goicoechea
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
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30
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Friedrich A, Eyselein J, Langer J, Färber C, Harder S. Cationic Heterobimetallic Mg(Zn)/Al(Ga) Combinations for Cooperative C-F Bond Cleavage. Angew Chem Int Ed Engl 2021; 60:16492-16499. [PMID: 33979476 PMCID: PMC8361950 DOI: 10.1002/anie.202103250] [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: 03/05/2021] [Indexed: 12/14/2022]
Abstract
Low-valent (Me BDI)Al and (Me BDI)Ga and highly Lewis acidic cations in [(tBu BDI)M+ ⋅C6 H6 ][(B(C6 F5 )4 - ] (M=Mg or Zn, Me BDI=HC[C(Me)N-DIPP]2 , tBu BDI=HC[C(tBu)N-DIPP]2 , DIPP=2,6-diisopropylphenyl) react to heterobimetallic cations [(tBu BDI)Mg-Al(Me BDI)+ ], [(tBu BDI)Mg-Ga(Me BDI)+ ] and [(tBu BDI)Zn-Ga(Me BDI)+ ]. These cations feature long Mg-Al (or Ga) bonds while the Zn-Ga bond is short. The [(tBu BDI)Zn-Al(Me BDI)+ ] cation was not formed. Combined AIM and charge calculations suggest that the metal-metal bonds to Zn are considerably more covalent, whereas those to Mg should be described as weak AlI (or GaI )→Mg2+ donor bonds. Failure to isolate the Zn-Al combination originates from cleavage of the C-F bond in the solvent fluorobenzene to give (tBu BDI)ZnPh and (Me BDI)AlF+ which is extremely Lewis acidic and was not observed, but (Me BDI)Al(F)-(μ-F)-(F)Al(Me BDI)+ was verified by X-ray diffraction. DFT calculations show that the remarkably facile C-F bond cleavage follows a dearomatization/rearomatization route.
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Affiliation(s)
- Alexander Friedrich
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Jonathan Eyselein
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Jens Langer
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Christian Färber
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Sjoerd Harder
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
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31
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Friedrich A, Eyselein J, Langer J, Färber C, Harder S. Cationic Heterobimetallic Mg(Zn)/Al(Ga) Combinations for Cooperative C–F Bond Cleavage. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103250] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Alexander Friedrich
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Jonathan Eyselein
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Jens Langer
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Christian Färber
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
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32
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Thum K, Martin J, Elsen H, Eyselein J, Stiegler L, Langer J, Harder S. Lewis Acidic Cationic Strontium and Barium Complexes. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100345] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Katharina Thum
- Chair of Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstraße 1 91058 Erlangen Germany
| | - Johannes Martin
- Chair of Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstraße 1 91058 Erlangen Germany
| | - Holger Elsen
- Chair of Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstraße 1 91058 Erlangen Germany
| | - Jonathan Eyselein
- Chair of Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstraße 1 91058 Erlangen Germany
| | - Lena Stiegler
- Chair of Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstraße 1 91058 Erlangen Germany
| | - Jens Langer
- Chair of Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstraße 1 91058 Erlangen Germany
| | - Sjoerd Harder
- Chair of Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstraße 1 91058 Erlangen Germany
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33
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Liu H, Schwamm RJ, Hill MS, Mahon MF, McMullin CL, Rajabi NA. Ambiphilic Al−Cu Bonding. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202104658] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Han‐Ying Liu
- Department of Chemistry University of Bath Bath BA2 7AY UK
| | | | | | - Mary F. Mahon
- Department of Chemistry University of Bath Bath BA2 7AY UK
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Liu HY, Schwamm RJ, Hill MS, Mahon MF, McMullin CL, Rajabi NA. Ambiphilic Al-Cu Bonding. Angew Chem Int Ed Engl 2021; 60:14390-14393. [PMID: 33899319 PMCID: PMC8252794 DOI: 10.1002/anie.202104658] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Indexed: 11/07/2022]
Abstract
Copper-alumanyl complexes, [LCu-Al(SiNDipp )], where L=carbene=NHCiPr (N,N'-diisopropyl-4,5-dimethyl-2-ylidene) and Me2 CAAC (1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethyl-pyrrolidin-2-ylidene) and featuring unsupported Al-Cu bonds, have been prepared. Divergent reactivity observed with carbodiimides and CO2 implies an ambiphilicity in the Cu-Al interaction that is dependent on the identity of the carbene co-ligand.
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Affiliation(s)
- Han-Ying Liu
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Ryan J Schwamm
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Michael S Hill
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | - Mary F Mahon
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
| | | | - Nasir A Rajabi
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK
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35
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Gentner TX, Mulvey RE. Alkali-Metal Mediation: Diversity of Applications in Main-Group Organometallic Chemistry. Angew Chem Int Ed Engl 2021; 60:9247-9262. [PMID: 33017511 PMCID: PMC8247348 DOI: 10.1002/anie.202010963] [Citation(s) in RCA: 95] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Indexed: 12/23/2022]
Abstract
Organolithium compounds have been at the forefront of synthetic chemistry for over a century, as they mediate the synthesis of myriads of compounds that are utilised worldwide in academic and industrial settings. For that reason, lithium has always been the most important alkali metal in organometallic chemistry. Today, that importance is being seriously challenged by sodium and potassium, as the alkali-metal mediation of organic reactions in general has started branching off in several new directions. Recent examples covering main-group homogeneous catalysis, stoichiometric organic synthesis, low-valent main-group metal chemistry, polymerization, and green chemistry are showcased in this Review. Since alkali-metal compounds are often not the end products of these applications, their roles are rarely given top billing. Thus, this Review has been written to alert the community to this rising unifying phenomenon of "alkali-metal mediation".
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Affiliation(s)
- Thomas X. Gentner
- Department of Pure and Applied ChemistryUniversity of StrathclydeGlasgowG1 1XLUK
| | - Robert E. Mulvey
- Department of Pure and Applied ChemistryUniversity of StrathclydeGlasgowG1 1XLUK
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36
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Abstract
Main group carbonyl analogues (R2 E=O) derived from p-block elements (E=groups 13 to 15) have long been considered as elusive species. Previously, employment of chemical tricks such as acid- and base-stabilization protocols granted access to these transient species in their masked forms. However, electronic and steric effects inevitably perturb their chemical reactivity and distinguish them from classical carbonyl compounds. A new era was marked by the recent isolation of acid-base free main group carbonyl analogues, ranging from a lighter boracarbonyl to the heavier silacarbonyls, phosphacarbonyls and a germacarbonyl. Most importantly, their unperturbed nature elicits exciting new chemistry, spanning the vista from classical organic carbonyl-type reactions to transition metal-like oxide ion transfer chemistry. In this Review, we survey the strategies used for the isolation of such systems and document their emerging reactivity profiles, with a view to providing fundamental comparisons both with carbon and transition metal oxo species. This highlights the emerging opportunities for exciting "crossover" reactivity offered by these derivatives of the p-block elements.
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Affiliation(s)
- Ying Kai Loh
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Simon Aldridge
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
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37
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Zheng X, Heilmann A, McManus C, Aldridge S. A Xanthene-Based Mono-Anionic PON Ligand: Exploiting a Bulky, Electronically Unsymmetrical Donor in Main Group Chemistry. Chemistry 2021; 27:3159-3165. [PMID: 33200850 PMCID: PMC7898390 DOI: 10.1002/chem.202004741] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/16/2020] [Indexed: 12/05/2022]
Abstract
The synthesis of a novel mono-anionic phosphino-amide ligand based on a xanthene backbone is reported, togetherr with the corresponding GaI complex, (PON)Ga (PON = 4-(di(2,4,6-trimethylphenyl)phosphino)-5-(2,6-diisopropylanilido)-2,7-di-tert-butyl-9,9-dimethylxanthene). The solid-state structure of (PON)Ga (obtained from X-ray crystallography) reveals very weak O⋅⋅⋅Ga and P⋅⋅⋅Ga interactions, consistent with a R2 NGa fragment which closely resembles those found in one-coordinate amidogallium systems. Strong N-to-Ga π donation from the amido substituent is reflected in a very short N-Ga distance (1.961(2) Å), while the P⋅⋅⋅Ga contact (3.076(1) Å) is well outside the sum of the respective covalent radii. While the donor properties of the PON ligand towards GaI are highly unsymmetrical, oxidation to GaIII leads to much stronger coordination of the pendant phosphine as shown by P-Ga distances which are up to 20 % shorter. From a steric perspective, the PON ligand is shown to be significantly bulkier than related β-diketiminate systems, a finding consistent with reactions of (PON)Ga towards O-atom sources that proceed without oligomerization. Despite this, the enhanced P-donor properties brought about by oxidation at gallium are not sufficient to quench the reactivity of the highly polar Ga-O unit. Instead, intramolecular benzylic C-H activation is observed across the Ga-O bond of a transient gallanone intermediate.
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Affiliation(s)
- Xiongfei Zheng
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Andreas Heilmann
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Caitilín McManus
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Simon Aldridge
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
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38
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Protchenko AV, Vasko P, Fuentes MÁ, Hicks J, Vidovic D, Aldridge S. Approaching a "Naked" Boryl Anion: Amide Metathesis as a Route to Calcium, Strontium, and Potassium Boryl Complexes. Angew Chem Int Ed Engl 2021; 60:2064-2068. [PMID: 33026153 PMCID: PMC7894291 DOI: 10.1002/anie.202011839] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Indexed: 11/08/2022]
Abstract
Amide metathesis has been used to generate the first structurally characterized boryl complexes of calcium and strontium, {(Me3 Si)2 N}M{B(NDippCH)2 }(thf)n (M=Ca, n=2; M=Sr, n=3), through the reactions of the corresponding bis(amides), M{N(SiMe3 )2 }2 (thf)2 , with (thf)2 Li- {B(NDippCH)2 }. Most notably, this approach can also be applied to the analogous potassium amide K{N(SiMe3 )2 }, leading to the formation of the solvent-free borylpotassium dimer [K{B(NDippCH)2 }]2 , which is stable in the solid state at room temperature for extended periods (48 h). A dimeric structure has been determined crystallographically in which the K+ cations interact weakly with both the ipso-carbons of the flanking Dipp groups and the boron centres of the diazaborolyl heterocycles, with K⋅⋅⋅B distances of >3.1 Å. These structural features, together with atoms in molecules (QTAIM) calculations imply that the boron-containing fragment closely approaches a limiting description as a "free" boryl anion in the condensed phase.
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Affiliation(s)
- Andrey V. Protchenko
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Petra Vasko
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
- Department of Chemistry, Nanoscience CenterUniversity of JyväskyläP. O. Box 3540014JyväskyläFinland
| | - M. Ángeles Fuentes
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Jamie Hicks
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Dragoslav Vidovic
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Simon Aldridge
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
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39
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Falconer RL, Nichol GS, Smolyar IV, Cockroft SL, Cowley MJ. Reversible Reductive Elimination in Aluminum(II) Dihydrides. Angew Chem Int Ed Engl 2021; 60:2047-2052. [PMID: 33022874 PMCID: PMC7894477 DOI: 10.1002/anie.202011418] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/05/2020] [Indexed: 11/12/2022]
Abstract
Oxidative addition and reductive elimination are defining reactions of transition‐metal organometallic chemistry. In main‐group chemistry, oxidative addition is now well‐established but reductive elimination reactions are not yet general in the same way. Herein, we report dihydrodialanes supported by amidophosphine ligands. The ligand serves as a stereochemical reporter for reversible reductive elimination/oxidative addition chemistry involving AlI and AlIII intermediates.
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Affiliation(s)
- Rosalyn L Falconer
- School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Gary S Nichol
- School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Ivan V Smolyar
- School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Scott L Cockroft
- School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Michael J Cowley
- School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
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40
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Protchenko AV, Vasko P, Fuentes MÁ, Hicks J, Vidovic D, Aldridge S. Approaching a “Naked” Boryl Anion: Amide Metathesis as a Route to Calcium, Strontium, and Potassium Boryl Complexes. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202011839] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Andrey V. Protchenko
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Petra Vasko
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
- Department of Chemistry, Nanoscience Center University of Jyväskylä P. O. Box 35 40014 Jyväskylä Finland
| | - M. Ángeles Fuentes
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Jamie Hicks
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Dragoslav Vidovic
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
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41
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Gentner TX, Mulvey RE. Alkalimetall‐Mediatoren: Vielfältige Anwendungen in der metallorganischen Chemie der Hauptgruppenelemente. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202010963] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Thomas X. Gentner
- Department of Pure and Applied Chemistry University of Strathclyde Glasgow G1 1XL Großbritannien
| | - Robert E. Mulvey
- Department of Pure and Applied Chemistry University of Strathclyde Glasgow G1 1XL Großbritannien
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42
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Falconer RL, Nichol GS, Smolyar IV, Cockroft SL, Cowley MJ. Reversible Reductive Elimination in Aluminum(II) Dihydrides. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202011418] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Rosalyn L. Falconer
- School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Gary S. Nichol
- School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Ivan V. Smolyar
- School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Scott L. Cockroft
- School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Michael J. Cowley
- School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
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43
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Hicks J, Vasko P, Heilmann A, Goicoechea JM, Aldridge S. Arene C-H Activation at Aluminium(I): meta Selectivity Driven by the Electronics of S N Ar Chemistry. Angew Chem Int Ed Engl 2020; 59:20376-20380. [PMID: 32722863 PMCID: PMC7693242 DOI: 10.1002/anie.202008557] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Indexed: 12/14/2022]
Abstract
The reactivity of the electron-rich anionic AlI aluminyl compound K2 [(NON)Al]2 (NON=4,5-bis(2,6-diisopropylanilido)-2,7-di-tert-butyl-9,9-dimethylxanthene) towards mono- and disubstituted arenes is reported. C-H activation chemistry with n-butylbenzene gives exclusively the product of activation at the arene meta position. Mechanistically, this transformation proceeds in a single step via a concerted Meisenheimer-type transition state. Selectivity is therefore based on similar electronic factors to classical SN Ar chemistry, which implies the destabilisation of transition states featuring electron-donating groups in either ortho or para positions. In the cases of toluene and the three isomers of xylene, benzylic C-H activation is also possible, with the product(s) formed reflecting the feasibility (or otherwise) of competing arene C-H activation at a site which is neither ortho nor para to a methyl substituent.
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Affiliation(s)
- Jamie Hicks
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
- Research School of ChemistryAustralian National University, Building 137Sullivan's Creek RoadActonACT2601Australia
| | - Petra Vasko
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
- Department of ChemistryNanoscience CenterUniversity of JyväskyläP. O. Box 3540014JyväskyläFinland
| | - Andreas Heilmann
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Jose M. Goicoechea
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
| | - Simon Aldridge
- Inorganic Chemistry LaboratoryDepartment of ChemistryUniversity of OxfordSouth Parks RoadOxfordOX1 3QRUK
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44
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Affiliation(s)
- Ying Kai Loh
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
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45
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Grams S, Eyselein J, Langer J, Färber C, Harder S. Boosting Low-Valent Aluminum(I) Reactivity with a Potassium Reagent. Angew Chem Int Ed Engl 2020; 59:15982-15986. [PMID: 32449816 PMCID: PMC7540686 DOI: 10.1002/anie.202006693] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Indexed: 12/11/2022]
Abstract
The reagent RK [R=CH(SiMe3 )2 or N(SiMe3 )2 ] was expected to react with the low-valent (DIPP BDI)Al (DIPP BDI=HC[C(Me)N(DIPP)]2 , DIPP=2,6-iPr-phenyl) to give [(DIPP BDI)AlR]- K+ . However, deprotonation of the Me group in the ligand backbone was observed and [H2 C=C(N-DIPP)-C(H)=C(Me)-N-DIPP]Al- K+ (1) crystallized as a bright-yellow product (73 %). Like most anionic AlI complexes, 1 forms a dimer in which formally negatively charged Al centers are bridged by K+ ions, showing strong K+ ⋅⋅⋅DIPP interactions. The rather short Al-K bonds [3.499(1)-3.588(1) Å] indicate tight bonding of the dimer. According to DOSY NMR analysis, 1 is dimeric in C6 H6 and monomeric in THF, but slowly reacts with both solvents. In reaction with C6 H6 , two C-H bond activations are observed and a product with a para-phenylene moiety was exclusively isolated. DFT calculations confirm that the Al center in 1 is more reactive than that in (DIPP BDI)Al. Calculations show that both AlI and K+ work in concert and determines the reactivity of 1.
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Affiliation(s)
- Samuel Grams
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Jonathan Eyselein
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Jens Langer
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Christian Färber
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Sjoerd Harder
- Chair of Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
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46
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Kurumada S, Sugita K, Nakano R, Yamashita M. A meta-Selective C-H Alumination of Mono-Substituted Benzene by Using An Alkyl-Substituted Al Anion through Hydride-Eliminating S N Ar Reaction. Angew Chem Int Ed Engl 2020; 59:20381-20384. [PMID: 32729647 DOI: 10.1002/anie.202009138] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Indexed: 11/10/2022]
Abstract
Reaction of an Al-centered anion with toluene proceeded to form C-H cleaved product with a perfect meta-selectivity and a relatively small kinetic isotope effect (KIE, kH /kD =1.51). DFT calculations suggested a two-step reaction mechanism and electronically controlled meta-selectivity arising from the electron-donating methyl group. The reaction with other mono-substituted arenes was also investigated.
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Affiliation(s)
- Satoshi Kurumada
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan
| | - Kengo Sugita
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan
| | - Ryo Nakano
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan
| | - Makoto Yamashita
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan
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47
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Kurumada S, Sugita K, Nakano R, Yamashita M. A
meta
‐Selective C−H Alumination of Mono‐Substituted Benzene by Using An Alkyl‐Substituted Al Anion through Hydride‐Eliminating S
N
Ar Reaction. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202009138] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Satoshi Kurumada
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8603 Japan
| | - Kengo Sugita
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8603 Japan
| | - Ryo Nakano
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8603 Japan
| | - Makoto Yamashita
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University, Furo-cho, Chikusa-ku Nagoya Aichi 464-8603 Japan
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48
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Hicks J, Vasko P, Heilmann A, Goicoechea JM, Aldridge S. Arene C−H Activation at Aluminium(I):
meta
Selectivity Driven by the Electronics of S
N
Ar Chemistry. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008557] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jamie Hicks
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
- Research School of Chemistry Australian National University, Building 137 Sullivan's Creek Road Acton ACT 2601 Australia
| | - Petra Vasko
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
- Department of Chemistry Nanoscience Center University of Jyväskylä P. O. Box 35 40014 Jyväskylä Finland
| | - Andreas Heilmann
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Jose M. Goicoechea
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
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49
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50
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Hicks J, Vasko P, Goicoechea JM, Aldridge S. The Aluminyl Anion: A New Generation of Aluminium Nucleophile. Angew Chem Int Ed Engl 2020; 60:1702-1713. [DOI: 10.1002/anie.202007530] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Indexed: 02/03/2023]
Affiliation(s)
- Jamie Hicks
- Research School of Chemistry Australian National University Sullivans Creek Road Acton 2601 Australia
| | - Petra Vasko
- Department of Chemistry Nanoscience Center University of Jyväskylä P. O. Box 35 Jyväskylä FI-40014 Finland
| | - Jose M. Goicoechea
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
| | - Simon Aldridge
- Inorganic Chemistry Laboratory Department of Chemistry University of Oxford South Parks Road Oxford OX1 3QR UK
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