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Thakur SK, Roig N, Monreal-Corona R, Langer J, Alonso M, Harder S. Similarities and Differences in Benzene Reduction with Ca, Sr, Yb and Sm: Strong Evidence for Tetra-Anionic Benzene. Angew Chem Int Ed Engl 2024; 63:e202405229. [PMID: 38613386 DOI: 10.1002/anie.202405229] [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: 03/16/2024] [Revised: 04/09/2024] [Accepted: 04/12/2024] [Indexed: 04/14/2024]
Abstract
Inverse sandwich complexes of Yb and Sm stabilized by a bulky β-diketiminate (BDI) ligand have been prepared: (BDI)Ln(η6,η6-C6H6)Ln(BDI); Ln=lanthanide. Coordinated benzene ligands can be neutral, di-anionic or, often controversially discussed, even tetra-anionic. The formal charge on benzene is correlated to assignment of the metal oxidation state which generally poses a problem. Herein, we take advantage of the structural similarities found when comparing CaII with YbII, and SrII with SmII complexes. In this work, we found an excellent overlap of the Ca/Yb inverse sandwich structures but a striking difference for the Sr/Sm pair. The much shorter Sm-N and Sm-C6H6 distances are strong evidence for a SmIII-benzene-4-SmIII assignment. This was further supported by NMR spectroscopy, magnetic susceptibility, reactivity and comprehensive computational investigation.
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Affiliation(s)
- Sandeep Kumar Thakur
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Nil Roig
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), 1050, Brussels, Belgium
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | - Roger Monreal-Corona
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), 1050, Brussels, Belgium
- Institut de Química Computacional i Catàlisi, Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003, Girona, Catalonia, Spain
| | - Jens Langer
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
| | - Mercedes Alonso
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), 1050, Brussels, Belgium
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry, Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058, Erlangen, Germany
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2
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Evans MJ, Mullins J, Mondal R, Jones C. Reductions of Arenes using a Magnesium-Dinitrogen Complex. Chemistry 2024; 30:e202401005. [PMID: 38622992 DOI: 10.1002/chem.202401005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 04/17/2024]
Abstract
In this contribution, we present "Birch-type", and other reductions of simple arenes by the potassium salt of an anionic magnesium dinitrogen complex, [{K(TCHPNON)Mg}2(μ-N2)] (TCHPNON=4,5-bis(2,4,6-tricyclohexylanilido)-2,7-diethyl-9,9-dimethyl-xanthene), which acts as a masked dimagnesium(I) diradical in these reactions. This reagent is non-hazardous, easy-to-handle, and in some cases provides access to 1,4-cyclohexadiene reduction products under relatively mild reaction conditions. This system works effectively to reduce benzene, naphthalene and anthracene through magnesium-bound "Birch-type" reduction intermediates. Cyclohexadiene products can be subsequently released from the magnesium centres by protonolysis with methanol. In contrast, the reduction of substituted arenes is less selective and involves competing reaction pathways. For toluene and 1,3,5-triphenylbenzene, the structural authentication of "Birch-type" reduction intermediates is conclusive, although the formation of corresponding 1,4-cyclohexadiene derivatives was low yielding. Reduction of anisole did not yield an isolable "Birch-type" intermediate, but instead gave a C-O activation product. Treating triphenylphosphine with [{K(TCHPNON)Mg}2(μ-N2)] resulted in the extrusion of both biphenyl and dinitrogen to afford a magnesium(II) phosphanide [{K(TCHPNON)Mg(μ-PPh2)}2]. Reduction of fluorobenzene proceeded via C-F activation of the arene, and isolation of the magnesium(II) fluoride [{K(TCHPNON)Mg(μ-F)}2]. Finally, the two-electron reduction of 1,3,5,7-cyclooctatetraene (COT) with [{K(TCHPNON)Mg}2(μ-N2)] yielded a complex, [{K(TCHPNON)Mg}2(μ-COT)], incorporating the aromatic dianion (COT2-).
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Affiliation(s)
- Matthew J Evans
- School of Chemistry, Monash University, PO Box 23, 3800, Melbourne, Victoria, Australia
| | - Jeremy Mullins
- School of Chemistry, Monash University, PO Box 23, 3800, Melbourne, Victoria, Australia
| | - Rahul Mondal
- School of Chemistry, Monash University, PO Box 23, 3800, Melbourne, Victoria, Australia
| | - Cameron Jones
- School of Chemistry, Monash University, PO Box 23, 3800, Melbourne, Victoria, Australia
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Duneş G, Cordier M, Kahlal S, Pöllnitz A, Saillard JY, Silvestru C, Sarazin Y. C-H bond activation at antimony(III): synthesis and reactivity of Sb(III)-oxyaryl species. Dalton Trans 2024. [PMID: 38868997 DOI: 10.1039/d4dt01400f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
We report on the synthesis, structure and reactivity of [{NCNMe4}Sb(C6H2-tBu2-3,5-O-4)] (3), an organoantimony(III)-oxyaryl species obtained upon Csp2-H bond activation in a phenolate ligand and stabilised by the monoanionic pincer {NCNMe4}-. The mechanism leading to the formation of 3 is highly sensitive to steric considerations. It was probed experimentally and by DFT calculations, and a number of intermediates and related complexes were identified. All data agree with successive heterolytic bond cleaving and bond forming processes involving charged species, rather than a pathway involving free radicals as previously exemplified with congeneric bismuth species. The nucleophilic behaviour of the oxyaryl ligand in 3, a complex that features both zwitterionic and quinoidal attributes, was illustrated in derivatisation reactions. In particular, insertion of CS2 in the Sb-Coxyaryl bond generates [{NCNMe4}Sb(S2C-C6H2-tBu2-3,5-O-4)].
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Affiliation(s)
- Gabriel Duneş
- Université de Rennes, CNRS, Institut des Sciences Chimiques de Rennes, UMR 6226, Campus de Beaulieu, 35042 Rennes, Cedex, France.
- Department of Chemistry, Supramolecular Organic and Organometallic Chemistry Centre (SOOMCC), Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos, 400028 Cluj-Napoca, Romania.
| | - Marie Cordier
- Université de Rennes, CNRS, Institut des Sciences Chimiques de Rennes, UMR 6226, Campus de Beaulieu, 35042 Rennes, Cedex, France.
| | - Samia Kahlal
- Université de Rennes, CNRS, Institut des Sciences Chimiques de Rennes, UMR 6226, Campus de Beaulieu, 35042 Rennes, Cedex, France.
| | - Alpar Pöllnitz
- Department of Chemistry, Supramolecular Organic and Organometallic Chemistry Centre (SOOMCC), Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos, 400028 Cluj-Napoca, Romania.
| | - Jean-Yves Saillard
- Université de Rennes, CNRS, Institut des Sciences Chimiques de Rennes, UMR 6226, Campus de Beaulieu, 35042 Rennes, Cedex, France.
| | - Cristian Silvestru
- Department of Chemistry, Supramolecular Organic and Organometallic Chemistry Centre (SOOMCC), Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, 11 Arany Janos, 400028 Cluj-Napoca, Romania.
| | - Yann Sarazin
- Université de Rennes, CNRS, Institut des Sciences Chimiques de Rennes, UMR 6226, Campus de Beaulieu, 35042 Rennes, Cedex, France.
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Wang Y, Zhang Y, Liang J, Tan B, Deng C, Huang W. Neutral inverse-sandwich rare-earth metal complexes of the benzene tetraanion. Chem Sci 2024; 15:8740-8749. [PMID: 38899277 PMCID: PMC11185217 DOI: 10.1039/d4sc02491e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 05/11/2024] [Indexed: 06/21/2024] Open
Abstract
Rare-earth metal complexes of the parent benzene tetraanion and neutral inverse-sandwich rare-earth metal arene complexes have remained elusive. Here, we report the first neutral inverse-sandwich rare-earth metal complexes of the parent benzene tetraanion supported by a monoanionic β-diketiminate (BDI) ligand. Reduction of the trivalent rare-earth metal diiodide precursors (BDI)MI2(THF) (BDI = HC(C(Me)N[C6H3-(3-pentyl)2-2,6])2; M = Y, 1-Y; M = Sm, 1-Sm) in benzene or para-xylene by potassium graphite yielded the neutral inverse-sandwich rare-earth metal arene complexes [(BDI)M(THF) n ]2(μ-η6,η6-arene) (M = Y, Sm; arene = benzene, 2-M; arene = para-xylene, 3-M). Single crystal X-ray diffraction, spectroscopic and magnetic characterization studies, together with density functional theory (DFT) calculations confirm that these neutral rare-earth metal arene complexes possess an [M3+-(arene)4--M3+] electronic structure with strong metal-arene δ interactions. The arene exchange reactivity shows that 2-Sm has higher stability than 3-Sm. Furthermore, 2-Sm can behave as a four-electron reductant to reduce unsaturated organic substrates. Particularly, while the reaction of 2-Sm with 1,3,5,7-cyclooctatetraene (COT) yielded (BDI)Sm(η8-COT) (4-Sm), 2-Sm reacted with 1,4-diphenylbutadiyne to afford (BDI)Sm(η4-C4Ph2) (5-Sm), the first rare-earth metallacyclopentatriene complex.
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Affiliation(s)
- Yi Wang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University Beijing 100871 P. R. China
| | - Yurou Zhang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University Beijing 100871 P. R. China
| | - Jiefeng Liang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University Beijing 100871 P. R. China
| | - Bowen Tan
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University Beijing 100871 P. R. China
| | - Chong Deng
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University Beijing 100871 P. R. China
| | - Wenliang Huang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University Beijing 100871 P. R. China
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5
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Sreedharan R, Gandhi T. Masters of Mediation: MN(SiMe 3) 2 in Functionalization of C(sp 3)-H Latent Nucleophiles. Chemistry 2024; 30:e202400435. [PMID: 38497321 DOI: 10.1002/chem.202400435] [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: 01/31/2024] [Revised: 03/16/2024] [Accepted: 03/18/2024] [Indexed: 03/19/2024]
Abstract
Organoalkali compounds have undergone a far-reaching transformation being a coupling partner to a mediator in unusual organic conversions which finds its spot in the field of sustainable synthesis. Transition-metal catalysis has always been the priority in C(sp3)-H bond functionalization, however alternatively, in recent times this has been seriously challenged by earth-abundant alkali metals and their complexes arriving at new sustainable organometallic reagents. In this line, the importance of MN(SiMe3)2 (M=Li, Na, K & Cs) reagent revived in C(sp3)-H bond functionalization over recent years in organic synthesis is showcased in this minireview. MN(SiMe3)2 reagent with higher reactivity, enhanced stability, and bespoke cation-π interaction have shown eye-opening mediated processes such as C(sp3)-C(sp3) cross-coupling, radical-radical cross-coupling, aminobenzylation, annulation, aroylation, and other transformations to utilize readily available petrochemical feedstocks. This article also emphasizes the unusual reactivity of MN(SiMe3)2 reagent in unreactive and robust C-X (X=O, N, F, C) bond cleavage reactions that occurred alongside the C(sp3)-H bond functionalization. Overall, this review encourages the community to exploit the untapped potential of MN(SiMe3)2 reagent and also inspires them to take up this subject to even greater heights.
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Affiliation(s)
- Ramdas Sreedharan
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
| | - Thirumanavelan Gandhi
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
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Evans MJ, Jones C. Low oxidation state and hydrido group 2 complexes: synthesis and applications in the activation of gaseous substrates. Chem Soc Rev 2024; 53:5054-5082. [PMID: 38595211 DOI: 10.1039/d4cs00097h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Numerous industrial processes utilise gaseous chemical feedstocks to produce useful chemical products. Atmospheric and other small molecule gases, including anthropogenic waste products (e.g. carbon dioxide), can be viewed as sustainable building blocks to access value-added chemical commodities and materials. While transition metal complexes have been well documented in the reduction and transformation of these substrates, molecular complexes of the terrestrially abundant alkaline earth metals have also demonstrated promise with remarkable reactivity reported towards an array of industrially relevant gases over the past two decades. This review covers low oxidation state and hydrido group 2 complexes and their role in the reduction and transformation of a selection of important gaseous substrates towards value-added chemical products.
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Affiliation(s)
- Matthew J Evans
- School of Chemistry, Monash University, PO Box 23, Melbourne, Victoria, 3800, Australia.
| | - Cameron Jones
- School of Chemistry, Monash University, PO Box 23, Melbourne, Victoria, 3800, Australia.
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Townrow OPE, Färber C, Zenneck U, Harder S. Metal Vapour Synthesis of an Organometallic Barium(0) Synthon. Angew Chem Int Ed Engl 2023:e202318428. [PMID: 38078903 DOI: 10.1002/anie.202318428] [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: 12/01/2023] [Indexed: 12/23/2023]
Abstract
A hydrocarbon-soluble barium anthracene complex was prepared by means of metal vapour synthesis. Reaction of 9,10-bis(trimethylsilyl)anthracene (Anth'') with barium vapour gave deep purple Ba(Anth'') which after extraction with diethyl ether crystallised as the cyclic octamer [Ba(Anth'')⋅Et2 O]8 . Dissolution in benzene or toluene led to replacement of the Et2 O ligand with a softer arene ligand and isolation of Ba(Anth'')⋅arene. Diffusion ordered spectroscopy (DOSY NMR ) measurements in benzene-d6 indicate solution species with a molecular weight that equals a trimeric constitution. Natural population analysis (NPA) assigned charges of +1.70 and -1.70 to Ba and Anth'', respectively, relating to highly ionic Ba2+ /Anth''2- bonding. Preliminary reactivity studies with air, Ph2 C=NPh, or H2 show that the complex reacts as a Ba0 synthon by release of neutral Anth''. This soluble molecular Ba0 /BaII redox synthon provides new routes for the syntheses of barium complexes under mild conditions.
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Affiliation(s)
- Oliver P E Townrow
- 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
| | - Ulrich Zenneck
- 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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8
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Harder S, Langer J. Opportunities with calcium Grignard reagents and other heavy alkaline-earth organometallics. Nat Rev Chem 2023; 7:843-853. [PMID: 37935796 DOI: 10.1038/s41570-023-00548-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2023] [Indexed: 11/09/2023]
Abstract
More than a century old, magnesium Grignard reagents remain essential to the toolbox of organic chemists. Although similar reagents with the neighbouring group 2 metal Ca have been explored, the considerably higher polarity and reactivity of the Ca-C bond result in undesired decomposition pathways. Ca Grignard reagents have found academic interest but have never fully developed into an established synthetic tool. Recent research activities, however, provide facile access to these highly reactive organocalcium species, including in situ preparation and ball milling approaches to tackle the challenge of controlling their extreme sensitivity. Heavier Grignard reagents are not just more reactive but profit from unique chemical transformations. Insight into the transition metal-like properties of Ca, Sr and Ba is only just emerging. Considering the rapidly developing field of alkaline-earth metal-mediated catalysis, heavy Grignard reagents will probably have a bright future.
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Affiliation(s)
- Sjoerd Harder
- Inorganic Chemistry, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany.
| | - Jens Langer
- Inorganic Chemistry, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
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Pearce KG, Dinoi C, Schwamm RJ, Maron L, Mahon MF, Hill MS. Variable Ca-C aryl Hapticity and its Consequences in Arylcalcium Dimers. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2304765. [PMID: 37715248 PMCID: PMC10625118 DOI: 10.1002/advs.202304765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/11/2023] [Indexed: 09/17/2023]
Abstract
The dimeric β-diketiminato calcium hydride, [(Dipp BDI)CaH]2 (Dipp BDI = HC{(Me)CN-2,6-i-Pr2 C6 H3 }2 ), reacts with ortho-, meta- or para-tolyl mercuric compounds to afford hydridoarylcalcium compounds, [(Dipp BDI)2 Ca2 (μ-H)(μ-o-,m-,p-tolyl)], in which dimer propagation occurs either via μ2 -η1 -η1 or μ2 -η1 -η6 bridging between the calcium centers. In each case, the orientation and hapticity of the aryl units is dependent upon the position of the methyl substituent. While wholly organometallic meta- and para-tolyl dimers, [(Dipp BDI)Ca(m-tolyl)]2 and [(Dipp BDI)Ca(p-tolyl)]2 , can be prepared and are stable, the ortho-tolyl isomer is prone to isomerization to a calcium benzyl analog. Computational analysis of this latter process with density functional theory (DFT) highlights an unusual mechanism invoking the generation of an intermediate dicalcium species in which the group 2 centers are bridged by a toluene dianion formed by the formal attachment of the original hydride anion to the initially generated ortho-tolyl substituent. Use of a more sterically encumbered aryl substituent, {3,5-t-Bu2 C6 H3 }, facilitates the selective formation of [(Dipp BDI)Ca(μ-H)(μ-3,5-t-Bu2 C6 H3 )Ca(Dipp BDI)], which can be converted into the unsymmetrically-substituted σ-aryl calcium complexes, [(Dipp BDI)Ca(μ-Ph)(μ-3,5-t-Bu2 C6 H3 )Ca(Dipp BDI)] and [(Dipp BDI)Ca(μ-p-tolyl)(μ-3,5-t-Bu2 C6 H3 )Ca(Dipp BDI)] by reaction with the appropriate mercuric diaryl. Conversion of [(Dipp BDI)Ca(H)(Ph)Ca(Dipp BDI)] to afford [{{(Dipp BDI)Ca}2 (μ2 -Cl)}2 (C6 H5 -C6 H5 )], comprising a biphenyl dianion, is also reported. Although this latter transformation is serendipitous, AIM analysis highlights that, in a related manner to the ortho-tolyl to benzyl isomerization, the requisite C-C coupling may be facilitated in an "across dimer" fashion by the experimentally-observed polyhapto engagement of the aryl substituents with each calcium.
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Affiliation(s)
- Kyle G. Pearce
- Department of ChemistryUniversity of BathClaverton DownBathBA2 7AYUK
| | - Chiara Dinoi
- Université de Toulouse et CNRSINSAUPSUMR 5215LPCNO135 Avenue de RangueilToulouseF‐31077France
| | - Ryan J. Schwamm
- Department of ChemistryUniversity of BathClaverton DownBathBA2 7AYUK
| | - Laurent Maron
- Université de Toulouse et CNRSINSAUPSUMR 5215LPCNO135 Avenue de RangueilToulouseF‐31077France
| | - Mary F. Mahon
- Department of ChemistryUniversity of BathClaverton DownBathBA2 7AYUK
| | - Michael S. Hill
- Department of ChemistryUniversity of BathClaverton DownBathBA2 7AYUK
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Mai J, Rösch B, Patel N, Langer J, Harder S. On the existence of low-valent magnesium-calcium complexes. Chem Sci 2023; 14:4724-4734. [PMID: 37181774 PMCID: PMC10171184 DOI: 10.1039/d3sc00909b] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 04/13/2023] [Indexed: 05/16/2023] Open
Abstract
DFT-Calculations predict that a low-valent complex (BDI)Mg-Ca(BDI) with bulky β-diketiminate (BDI) ligands is thermodynamically stable. It was attempted to isolate such a complex by salt-metathesis between [(DIPePBDI*)Mg-Na+]2 and [(DIPePBDI)CaI]2 (DIPePBDI = HC[C(Me)N-DIPeP]2; DIPePBDI* = HC[C(tBu)N-DIPeP]2; DIPeP = 2,6-CH(Et)2-phenyl). Whereas in alkane solvents no reaction was observed, salt-metathesis in C6H6 led to immediate C-H activation of benzene to give (DIPePBDI*)MgPh and (DIPePBDI)CaH, the latter crystallizing as a THF-solvated dimer [(DIPePBDI)CaH·THF]2. Calculations suggest reduction and insertion of benzene in the Mg-Ca bond. The activation enthalpy for the subsequent decomposition of C6H62- into Ph- and H- is only 14.4 kcal mol-1. Repeating this reaction in the presence of naphthalene or anthracene led to heterobimetallic complexes in which naphthalene2- or anthracene2- anions are sandwiched between (DIPePBDI*)Mg+ and (DIPePBDI)Ca+ cations. These complexes slowly decompose to their homometallic counterparts and further decomposition products. Complexes in which naphthalene2- or anthracene2- anions are sandwiched between two (DIPePBDI)Ca+ cations were isolated. The low-valent complex (DIPePBDI*)Mg-Ca(DIPePBDI) could not be isolated due to its high reactivity. There is, however, strong evidence that this heterobimetallic compound is a fleeting intermediate.
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Affiliation(s)
- Jonathan Mai
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstraße 1 Erlangen 91058 Germany
| | - Bastian Rösch
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstraße 1 Erlangen 91058 Germany
| | - Neha Patel
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstraße 1 Erlangen 91058 Germany
| | - Jens Langer
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstraße 1 Erlangen 91058 Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstraße 1 Erlangen 91058 Germany
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