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Kohl SJ, Sigmund LM, Schmitt M, Greb L. Nitrogen monoxide and calix[4]pyrrolato aluminate: structural constraint enabled NO dimerization. Chem Sci 2024; 15:10803-10809. [PMID: 39027292 PMCID: PMC11253113 DOI: 10.1039/d4sc02378a] [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: 04/10/2024] [Accepted: 06/15/2024] [Indexed: 07/20/2024] Open
Abstract
The dimerization of nitrogen monoxide (NO) is highly relevant in homo- and heterogeneous biochemical and environmental redox processes, but a broader understanding is challenged by the endergonic nature of this equilibrium. The present work describes NO-dimerization leveraged by structurally constrained aluminum and metal-ligand cooperativity at the anionic calix[4]pyrrolato aluminate(III). Quantum chemical calculations reveal the driving force for N-N bond formation, while reactivity tests shed light on subsequent redox chemistry and NO decomposition at metal surfaces. Inhibiting the dimerization pathway by saturating NO's unpaired electron with a phenyl group (nitrosobenzene) allows trapping the 1,2-adduct as a key intermediate. Elevated temperatures result in an unprecedented and high-yielding rearrangement of the calix[4]pyrrolato ligand scaffold. Kinetic and theoretical studies provide a comprehensive picture of the rearrangement mechanism and delineate systematics for ring modification of the prominent calix[4]pyrrole macrocycle.
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Affiliation(s)
- Senta J Kohl
- Anorganisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Lukas M Sigmund
- Anorganisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Manuel Schmitt
- Anorganisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Lutz Greb
- Anorganisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
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2
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Sinha S, Giri S. Ab initio investigation on the mechanism of SO 2 activation by P/B intermolecular frustrated Lewis pairs. J Mol Model 2024; 30:241. [PMID: 38954102 DOI: 10.1007/s00894-024-06038-4] [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: 04/03/2024] [Accepted: 06/20/2024] [Indexed: 07/04/2024]
Abstract
CONTEXT In silico study investigates the activation of sulfur dioxide by newly designed frustrated Lewis pairs, i.e., [P(tBu)3…B(C2NBSHF2)3], where the Lewis acid part is a super Lewis acid. The activation process involves the making of P-S and B-O bonds, leading to the formation of an FLP-SO2 adduct. The calculated results demonstrate that the activation of SO2 by the FLP is almost barrierless and exothermic. Exploration of the impact of the solvent environment on the feasibility and energetics of the reaction has been investigated. The exothermicity is increasing in nonpolar solvents. METHODS This study focuses on understanding the electronic activity of SO2 activation by FLP with the help of the Minnesota 06 functional, M06-2X (global hybrid functional with 54% HF exchange) along with Pople's basis set, 6-311G (d, p). Principal interacting orbital and extended transition state-natural orbitals for chemical valence studies, giving impactful insight into the favorable orbital interaction and electron transfer in this reaction. Furthermore, useful CDFT descriptors such as reaction force constant and reaction electronic flux profiles along the intrinsic reaction coordinate give insights into the synchronicity and total electronic activity of the reaction.
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Affiliation(s)
- Swapan Sinha
- School of Applied Science and Humanities, Haldia Institute of Technology, Haldia, 721657, India
- Maulana Abul Kalam Azad University of Technology, Haringhata, 741249, India
| | - Santanab Giri
- School of Applied Science and Humanities, Haldia Institute of Technology, Haldia, 721657, India.
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3
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Mondal H, Chattaraj PK. CO 2 reduction using aluminum hydride: Generation of in-situ frustrated Lewis pairs and small molecule activation therein. J Comput Chem 2024; 45:1098-1111. [PMID: 38261518 DOI: 10.1002/jcc.27285] [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: 11/02/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 01/25/2024]
Abstract
CO2 reduction is appealing for the long-term production of high-value fuels and chemicals. Herein, using density functional theory (DFT) based calculations, we study the CO2 reduction pathway to formic acid using aluminum hydride and phosphine derivatives. Our primary focus is on aluminum hydride derivatives, aimed at improving the efficiency of the CO2 reduction process. Substituents with σ-donating properties at the aluminum center are discovered to lower the activation barriers. We demonstrate how di-tert-butylphosphine oxide (LB-O)/di-tert-butylphosphine sulfide (LB-S)/di-tert-butylphosphanimine (LB-N) work together with aluminum hydride to facilitate CO2 reduction process and generate in-situ frustrated Lewis pairs (FLPs), such as FLP-O, FLP-S, and FLP-N. The activation strain model (ASM) analysis reveals the significance of strain energy in determining activation barriers. EDA-NOCV and PIO analyses elucidate the orbital interactions at the corresponding transition states. Furthermore, the study delves into the activation of various small molecules, such as dihydrogen, acetylene, ethylene, carbon dioxide, nitrous oxide, and acetonitrile, using those in-situ generated FLPs. The study highlights the low activation barriers and emphasizes the potential for small molecule activation in this context.
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Affiliation(s)
- Himangshu Mondal
- Department of Chemistry, Indian Institute of Technology, Kharagpur, India
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4
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Mondal H, Chattaraj PK. Unraveling Reactivity Pathways: Dihydrogen Activation and Hydrogenation of Multiple Bonds by Pyramidalized Boron-Based Frustrated Lewis Pairs. ChemistryOpen 2024; 13:e202300179. [PMID: 38117941 PMCID: PMC11004477 DOI: 10.1002/open.202300179] [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: 08/29/2023] [Revised: 11/24/2023] [Indexed: 12/22/2023] Open
Abstract
The activation of H2 by pyramidalized boron-based frustrated Lewis Pairs (FLPs) (B/E-FLP systems where "E" refers to N, P, As, Sb, and Bi) have been explored using density functional theory (DFT) based computational study. The activation pathway for the entire process is accurately characterized through the utilization of the activation strain model (ASM) of reactivity, shedding light on the underlying physical factors governing the process. The study also explores the hydrogenation process of multiple bonds with the help of B/N-FLP. The research findings demonstrate that the liberation of activated dihydrogen occurs in a synchronized, albeit noticeably asynchronous, fashion. The transformation is extensively elucidated using the activation strain model and the energy decomposition analysis. This approach suggests a co-operative double hydrogen-transfer mechanism, where the B-H hydride triggers a nucleophilic attack on the carbon atom of the multiple bonds, succeeded by the migration of the protic N-H.
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Affiliation(s)
- Himangshu Mondal
- Department of ChemistryIndian Institute of TechnologyKharagpur721302India
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5
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Sinha S, Giri S. In Silico Investigation of the Mechanism of Disulfide Bond Dissociation by New Frustrated Lewis Pairs. J Phys Chem A 2024; 128:97-106. [PMID: 38149919 DOI: 10.1021/acs.jpca.3c06351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
Understanding the mechanism of disulfide bond cleavage is important in various scientific disciplines including organic synthesis, catalysis, and biochemistry. In this study, an in silico investigation has been carried out for the dissociation of disulfide bonds using newly designed frustrated Lewis pairs (FLPs). The study revealed that the cleavage of the disulfide bond by the FLP P(tBu)3/B(C2NBSHF2)3 can also be used like the conventional FLP (tBu)3P/B(C6F5)3. It has been observed that the reaction is almost thermoneutral in the gas phase but exothermic in nonpolar solvents, such as toluene, heptane, and hexane. Furthermore, the natural bond orbital (NBO) describes insights into the role of FLPs in facilitating this reaction. Additionally, reaction force and force constant studies shed light on the energy requirements for completing the reaction and the synchronous nature of the dissociation process, respectively. Reaction electronic flux (REF) and its separations give the pattern of electronic activity during the chemical reaction. Extended transition state-natural orbitals for chemical valence (ETS-NOCV) and principal interacting orbital (PIO) analysis provide valuable information about the orbital interactions during the chemical reaction.
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Affiliation(s)
- Swapan Sinha
- School of Applied Science and Humanities, Haldia Institute of Technology, Haldia 721657, India
- Maulana Abul Kalam Azad University of Technology, Haringhata 741249, India
| | - Santanab Giri
- School of Applied Science and Humanities, Haldia Institute of Technology, Haldia 721657, India
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6
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Frenette BL, Rivard E. Frustrated Lewis Pair Chelation in the p-Block. Chemistry 2023; 29:e202302332. [PMID: 37677126 DOI: 10.1002/chem.202302332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/06/2023] [Accepted: 09/07/2023] [Indexed: 09/09/2023]
Abstract
Frustrated Lewis pairs (FLPs) have been the subject of considerable study since the field's inception. While much of the research into FLPs has centered around small molecule activation for diverse stoichiometric and catalytic transformations, intramolecular FLPs also show promise as chelating ligands. The cooperative action of Lewis basic and acidic moieties enables intramolecular FLPs to stabilize low oxidation state centers and (consequently) reactive molecular fragments through a donor-acceptor approach, making them an attractive ligand class in main group element chemistry. This review outlines the state of FLP chelation to date throughout the p-block, encompassing primarily groups 13-16.
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Affiliation(s)
- Brandon L Frenette
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta, T6G 2G2, Canada
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta, T6G 2G2, Canada
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Abstract
Nitroxides, also known as nitroxyl radicals, are long-lived or stable radicals with the general structure R1R2N-O•. The spin distribution over the nitroxide N and O atoms contributes to the thermodynamic stability of these radicals. The presence of bulky N-substituents R1 and R2 prevents nitroxide radical dimerization, ensuring their kinetic stability. Despite their reactivity toward various transient C radicals, some nitroxides can be easily stored under air at room temperature. Furthermore, nitroxides can be oxidized to oxoammonium salts (R1R2N═O+) or reduced to anions (R1R2N-O-), enabling them to act as valuable oxidants or reductants depending on their oxidation state. Therefore, they exhibit interesting reactivity across all three oxidation states. Due to these fascinating properties, nitroxides find extensive applications in diverse fields such as biochemistry, medicinal chemistry, materials science, and organic synthesis. This review focuses on the versatile applications of nitroxides in organic synthesis. For their use in other important fields, we will refer to several review articles. The introductory part provides a brief overview of the history of nitroxide chemistry. Subsequently, the key methods for preparing nitroxides are discussed, followed by an examination of their structural diversity and physical properties. The main portion of this review is dedicated to oxidation reactions, wherein parent nitroxides or their corresponding oxoammonium salts serve as active species. It will be demonstrated that various functional groups (such as alcohols, amines, enolates, and alkanes among others) can be efficiently oxidized. These oxidations can be carried out using nitroxides as catalysts in combination with various stoichiometric terminal oxidants. By reducing nitroxides to their corresponding anions, they become effective reducing reagents with intriguing applications in organic synthesis. Nitroxides possess the ability to selectively react with transient radicals, making them useful for terminating radical cascade reactions by forming alkoxyamines. Depending on their structure, alkoxyamines exhibit weak C-O bonds, allowing for the thermal generation of C radicals through reversible C-O bond cleavage. Such thermally generated C radicals can participate in various radical transformations, as discussed toward the end of this review. Furthermore, the application of this strategy in natural product synthesis will be presented.
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Affiliation(s)
- Dirk Leifert
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
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van der Zee LJ, Pahar S, Richards E, Melen RL, Slootweg JC. Insights into Single-Electron-Transfer Processes in Frustrated Lewis Pair Chemistry and Related Donor-Acceptor Systems in Main Group Chemistry. Chem Rev 2023; 123:9653-9675. [PMID: 37431868 PMCID: PMC10416219 DOI: 10.1021/acs.chemrev.3c00217] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Indexed: 07/12/2023]
Abstract
The activation and utilization of substrates mediated by Frustrated Lewis Pairs (FLPs) was initially believed to occur solely via a two-electron, cooperative mechanism. More recently, the occurrence of a single-electron transfer (SET) from the Lewis base to the Lewis acid was observed, indicating that mechanisms that proceed via one-electron-transfer processes are also feasible. As such, SET in FLP systems leads to the formation of radical ion pairs, which have recently been more frequently observed. In this review, we aim to discuss the seminal findings regarding the recently established insights into the SET processes in FLP chemistry as well as highlight examples of this radical formation process. In addition, applications of reported main group radicals will also be reviewed and discussed in the context of the understanding of SET processes in FLP systems.
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Affiliation(s)
- Lars J.
C. van der Zee
- Van
’t Hoff Institute for Molecular Sciences, University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands
| | - Sanjukta Pahar
- Cardiff
Catalysis Institute, Cardiff University, Translational Research Hub, Maindy
Road, Cathays, Cardiff, CF24 4HQ Wales, United Kingdom
| | - Emma Richards
- Cardiff
Catalysis Institute, Cardiff University, Translational Research Hub, Maindy
Road, Cathays, Cardiff, CF24 4HQ Wales, United Kingdom
| | - Rebecca L. Melen
- Cardiff
Catalysis Institute, Cardiff University, Translational Research Hub, Maindy
Road, Cathays, Cardiff, CF24 4HQ Wales, United Kingdom
| | - J. Chris Slootweg
- Van
’t Hoff Institute for Molecular Sciences, University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands
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Ghara M, Mondal H, Pal R, Chattaraj PK. Frustrated Lewis Pairs: Bonding, Reactivity, and Applications. J Phys Chem A 2023. [PMID: 37216335 DOI: 10.1021/acs.jpca.3c02141] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The outstanding capability of Frustrated Lewis Pair (FLP) catalysts to activate small molecules has gained significant attention in recent times. Reactivity of FLP is further extended toward the hydrogenation of various unsaturated species. Over the past decade, this unique catalysis concept has been successfully expanded to heterogeneous catalysis as well. The present review article gives a brief survey on several studies on this field. A thorough discussion on quantum chemical studies concerning the activation of H2 is provided. The role of aromaticity and boron-ligand cooperation on the reactivity of FLP is discussed in the Review. How FLP can activate other small molecules by cooperative action of its Lewis centers is also discussed. Further, the discussion is shifted to the hydrogenation of various unsaturated species and the mechanism regarding this process. It also discusses the latest theoretical advancements in the application of FLP in heterogeneous catalysis across various domains, such as two-dimensional materials, functionalized surfaces, and metal oxides. A deeper understanding of the catalytic process may assist in devising new heterogeneous FLP catalysts through experimental design.
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Affiliation(s)
- Manas Ghara
- Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India
| | - Himangshu Mondal
- Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India
| | - Ranita Pal
- Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur 721302, India
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10
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Zhang ZF, Su MD. Influence of the Element and Substituent Effects on the Reactivity of Catching Reactions of Difluorocarbene by Benzene-Bridged and Group-13/Group-15-Based Frustrated Lewis Pairs. Inorg Chem 2023; 62:1018-1031. [PMID: 36604303 DOI: 10.1021/acs.inorgchem.2c03968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The trapping reactions of CF2 by benzene-bridged Group-13/P-based and B/Group-15-based frustrated Lewis pairs (FLPs) have been computationally investigated based on density functional theory. Interestingly, our theoretical calculations predict that the capture of CF2 by all five Group-13/P-based FLPs is energetically feasible. However, in the B/Group-15-based FLPs, only the phosphorus-based B/P-FLP can trap CF2 from kinetic and thermodynamical viewpoints. According to the analyses of the activation strain model, it can be known that the atomic radius of the G15 element (Lewis base) of benzene-bridged B/Group-15-FLP plays an important role in controlling the reactivity of the CF2 catching reactions, whereas the atomic radius of the Group-13 center (Lewis acid) does not play a role in influencing the activation barrier of these CF2 catching reactions. Our theoretical findings based on sophisticated methods suggest that the forward bonding is the FLP-to-CF2 interaction, the LP (Group-15-donor) → vacant p-π-orbital (CF2), which was quantitatively proved to be strong in such present CF2 catching reactions. However, the back bonding is the CF2-to-FLP interaction, the empty σ-orbital (Group-13-acceptor) ← sp2-σ-orbital (CF2), which was verified to be relatively weak. Our theoretical pieces of evidence reveal that the stronger electron-donating ability of the substituents is attached to the Lewis basic center and can make the reaction barrier of the benzene-bridged Group-13/Group-15-based FLP-related compound catching CF2 smaller and more exothermic.
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Affiliation(s)
- Zheng-Feng Zhang
- Department of Applied Chemistry, National Chiayi University, Chiayi60004, Taiwan
| | - Ming-Der Su
- Department of Applied Chemistry, National Chiayi University, Chiayi60004, Taiwan.,Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung80708, Taiwan
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Dolai R, Kumar R, Elvers BJ, Pal PK, Joseph B, Sikari R, Nayak MK, Maiti A, Singh T, Chrysochos N, Jayaraman A, Krummenacher I, Mondal J, Priyakumar UD, Braunschweig H, Yildiz CB, Schulzke C, Jana A. Carbodicarbenes and Striking Redox Transitions of their Conjugate Acids: Influence of NHC versus CAAC as Donor Substituents. Chemistry 2023; 29:e202202888. [PMID: 36129127 PMCID: PMC10100033 DOI: 10.1002/chem.202202888] [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: 09/15/2022] [Indexed: 01/11/2023]
Abstract
Herein, a new type of carbodicarbene (CDC) comprising two different classes of carbenes is reported; NHC and CAAC as donor substituents and compare the molecular structure and coordination to Au(I)Cl to those of NHC-only and CAAC-only analogues. The conjugate acids of these three CDCs exhibit notable redox properties. Their reactions with [NO][SbF6 ] were investigated. The reduction of the conjugate acid of CAAC-only based CDC with KC8 results in the formation of hydrogen abstracted/eliminated products, which proceed through a neutral radical intermediate, detected by EPR spectroscopy. In contrast, the reduction of conjugate acids of NHC-only and NHC/CAAC based CDCs led to intermolecular reductive (reversible) carbon-carbon sigma bond formation. The resulting relatively elongated carbon-carbon sigma bonds were found to be readily oxidized. They were, thus, demonstrated to be potent reducing agents, underlining their potential utility as organic electron donors and n-dopants in organic semiconductor molecules.
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Affiliation(s)
- Ramapada Dolai
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - Rahul Kumar
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - Benedict J. Elvers
- Institut für BiochemieUniversität GreifswaldFelix-Hausdorff-Strasse 417489GreifswaldGermany
| | - Pradeep Kumar Pal
- International Institute of Information Technology GachibowliHyderabad500032India
| | - Benson Joseph
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - Rina Sikari
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - Mithilesh Kumar Nayak
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - Avijit Maiti
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - Tejender Singh
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - Nicolas Chrysochos
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - Arumugam Jayaraman
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Ivo Krummenacher
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Jagannath Mondal
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
| | - U. Deva Priyakumar
- International Institute of Information Technology GachibowliHyderabad500032India
| | - Holger Braunschweig
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Cem B. Yildiz
- Department of Aromatic and Medicinal PlantsAksaray UniversityAksaray68100Turkey
| | - Carola Schulzke
- Institut für BiochemieUniversität GreifswaldFelix-Hausdorff-Strasse 417489GreifswaldGermany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad GopanpallyHyderabad500046TelanganaIndia
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12
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Unveiling novel reactivity of P/Al frustrated Lewis pair: ring size-dependent activation of cyclic ethers/thioethers and CO2 insertion therein. J CHEM SCI 2022. [DOI: 10.1007/s12039-022-02119-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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13
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Hosseininasab V, DiMucci IM, Ghosh P, Bertke JA, Chandrasekharan S, Titus CJ, Nordlund D, Freed JH, Lancaster KM, Warren TH. Lewis acid-assisted reduction of nitrite to nitric and nitrous oxides via the elusive nitrite radical dianion. Nat Chem 2022; 14:1265-1269. [PMID: 36064970 PMCID: PMC9633411 DOI: 10.1038/s41557-022-01025-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 07/22/2022] [Indexed: 11/09/2022]
Abstract
Reduction of nitrite anions (NO2-) to nitric oxide (NO), nitrous oxide (N2O) and ultimately dinitrogen (N2) takes place in a variety of environments, including in the soil as part of the biogeochemical nitrogen cycle and in acidified nuclear waste. Nitrite reduction typically takes place within the coordination sphere of a redox-active transition metal. Here we show that Lewis acid coordination can substantially modify the reduction potential of this polyoxoanion to allow for its reduction under non-aqueous conditions (-0.74 V versus NHE). Detailed characterization confirms the formation of the borane-capped radical nitrite dianion (NO22-), which features a N(II) oxidation state. Protonation of the nitrite dianion results in the facile loss of nitric oxide (NO), whereas its reaction with NO results in disproportionation to nitrous oxide (N2O) and nitrite (NO2-). This system connects three redox levels in the global nitrogen cycle and provides fundamental insights into the conversion of NO2- to NO.
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Affiliation(s)
| | - Ida M DiMucci
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Pokhraj Ghosh
- Department of Chemistry, Georgetown University, Washington, DC, USA
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Washington, DC, USA
| | | | - Charles J Titus
- Department of Physics, Stanford University, Stanford, CA, USA
| | - Dennis Nordlund
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Jack H Freed
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA.
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Washington, DC, USA.
- Department of Chemistry, Michigan State University, East Lansing, MI, USA.
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14
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Sun X, Hinz A, Kucher H, Gamer MT, Roesky PW. Stereoselective Activation of Small Molecules by a Stable Chiral Silene. Chemistry 2022; 28:e202201963. [PMID: 35762907 DOI: 10.1002/chem.202201963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Indexed: 01/07/2023]
Abstract
The reaction of the dilithium salt of the enantiopure (S)-BINOL (1,1'-bi-2-naphthol) with two equivalents of the amidinate-stabilized chlorosilylene [LPh SiCl] (LPh =PhC(NtBu)2 ) led to the formation of the first example of a chiral cyclic silene species comprising an (S)-BINOL ligand. The reactivity of the Si=C bond was investigated by reaction with elemental sulfur, CO2 and HCl. The reaction with S8 led to a Si=C bond cleavage and concomitantly to a ring-opened product with imine and silanethione functional groups. The reaction with CO2 resulted in the cleavage of the CO2 molecule into a carbonyl group and an isolated O atom, while a new stereocenter is formed in a highly selective manner. According to DFT calculations, the [2+2] cycloaddition product is the key intermediate. Further reactivity studies of the chiral cyclic silene with HCl resulted in a stereoselective addition to the Si=C bond, while the fully selective formation of two stereocenters was achieved. The quantitative stereoselective addition of CO2 and HCl to a Si=C bond is unprecedented.
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Affiliation(s)
- Xiaofei Sun
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstraße 15, 76131, Karlsruhe, Germany
| | - Alexander Hinz
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstraße 15, 76131, Karlsruhe, Germany
| | - Hannes Kucher
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstraße 15, 76131, Karlsruhe, Germany
| | - Michael T Gamer
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstraße 15, 76131, Karlsruhe, Germany
| | - Peter W Roesky
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstraße 15, 76131, Karlsruhe, Germany
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Schulz J, Sárosi MB, Hey‐Hawkins E. Exploring the Reactivity of B-Connected Carboranylphosphines in Frustrated Lewis Pair Chemistry: A New Frame for a Classic System. Chemistry 2022; 28:e202200531. [PMID: 35472172 PMCID: PMC9320892 DOI: 10.1002/chem.202200531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Indexed: 11/15/2022]
Abstract
The primary phosphines MesPH2 and tBuPH2 react with 9-iodo-m-carborane yielding B9-connected secondary carboranylphosphines 1,7-H2 C2 B10 H9 -9-PHR (R=2,4,6-Me3 C6 H2 (Mes; 1 a), tBu (1 b)). Addition of tris(pentafluorophenyl)borane (BCF) to 1 a, b resulted in the zwitterionic compounds 1,7-H2 C2 B10 H9 -9-PHR(p-C6 F4 )BF(C6 F5 )2 (2 a, b) through nucleophilic para substitution of a C6 F5 ring followed by fluoride transfer to boron. Further reaction with Me2 SiHCl prompted a H-F exchange yielding the zwitterionic compounds 1,7-H2 C2 B10 H9 -9-PHR(p-C6 F4 )BH(C6 F5 )2 (3 a, b). The reaction of 2 a, b with one equivalent of R'MgBr (R'=Me, Ph) gave the extremely water-sensitive frustrated Lewis pairs 1,7-H2 C2 B10 H9 -9-PR(p-C6 F4 )B(C6 F5 )2 (4 a, b). Hydrolysis of the B-C6 F4 bond in 4 a, b gave the first tertiary B-carboranyl phosphines with three distinct substituents, 1,7-H2 C2 B10 H9 -9-PR(p-C6 F4 H) (5 a, b). Deprotonation of the zwitterionic compounds 2 a, b and 3 a, b formed anionic phosphines [1,7-H2 C2 B10 H9 -9-PR(p-C6 F4 )BX(C6 F5 )2 ]- [DMSOH]+ (R=Mes, X=F (6 a), R=tBu, X=F (6 b); R=Mes, X=H (7 a), R=tBu, X=H (7 b)). Reaction of 2 a, b with an excess of Grignard reagents resulted in the addition of R' at the boron atom yielding the anions [1,7-H2 C2 B10 H9 -9-PR(p-C6 F4 )BR'(C6 F5 )2 ]- (R=Mes, R'=Me (8 a), R=tBu, R'=Me (8 b); R=Mes, R'=Ph (9 a), R=tBu, R'=Ph (9 b)) with [MgBr(Et2 O)n ]+ as counterion. The ability of the zwitterionic compounds 3 a, b to hydrogenate imines as well as the Brønsted acidity of 3 a were investigated.
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Affiliation(s)
- Jan Schulz
- Leipzig University, Faculty of Chemistry and Mineralogy Institute of Inorganic ChemistryJohannisallee 2904103LeipzigGermany
| | - Menyhárt B. Sárosi
- Leipzig University, Faculty of Chemistry and Mineralogy Wilhelm-Ostwald-Institute for Physical and Theoretical ChemistryLinnéstraße 204103LeipzigGermany
| | - Evamarie Hey‐Hawkins
- Leipzig University, Faculty of Chemistry and Mineralogy Institute of Inorganic ChemistryJohannisallee 2904103LeipzigGermany
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16
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Mahaut D, Champagne B, Berionni G. Frustrated Lewis Pair Catalyzed Hydrogenation of Unactivated Alkenes With Sterically Hindered 9‐Phosphatriptycenes. ChemCatChem 2022. [DOI: 10.1002/cctc.202200294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Damien Mahaut
- University of Namur: Universite de Namur Chemistry BELGIUM
| | | | - Guillaume Berionni
- University of Namur: Universite de Namur Chemistry Department Rue de Bruxelles 61 5000 Namur BELGIUM
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17
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Mondal H, Patra SG, Chattaraj PK. Small molecule activation and dehydrogenation of an amine–borane system using frustrated Lewis pairs. Struct Chem 2022. [DOI: 10.1007/s11224-022-01934-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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18
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19
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Activation of Small Molecules and Hydrogenation of CO2 Catalyzed by Frustrated Lewis Pairs. Catalysts 2022. [DOI: 10.3390/catal12020201] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The chemistry of frustrated Lewis pair (FLP) is widely explored in the activation of small molecules, the hydrogenation of CO2, and unsaturated organic species. A survey of several experimental works on the activation of small molecules by FLPs and the related mechanistic insights into their reactivity from electronic structure theory calculation are provided in the present review, along with the catalytic hydrogenation of CO2. The mechanistic insight into H2 activation is thoroughly discussed, which may provide a guideline to design more efficient FLP for H2 activation. FLPs can activate other small molecules like, CO, NO, CO2, SO2, N2O, alkenes, alkynes, etc. by cooperative action of the Lewis centers of FLPs, as revealed by several computational analyses. The activation barrier of H2 and other small molecules by the FLP can be decreased by utilizing the aromaticity criterion in the FLP as demonstrated by the nucleus independent chemical shift (NICS) analysis. The term boron-ligand cooperation (BLC), which is analogous to the metal-ligand cooperation (MLC), is invoked to describe a distinct class of reactivity of some specific FLPs towards H2 activation.
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20
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Possible C-F bond activation by B(C6F5)3/lutidine and Al(C6F5)3/lutidine frustrated Lewis pair: an in silico study. J CHEM SCI 2022. [DOI: 10.1007/s12039-021-02010-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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21
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Chen C, Daniliuc CG, Klabunde S, Hansen MR, Kehr G, Erker G. Generation of Boryl-nitroxide Radicals from a Boraalkene via the Nitroso Ene Reaction. Chem Sci 2022; 13:10891-10896. [PMID: 36320693 PMCID: PMC9491209 DOI: 10.1039/d2sc02485c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 08/09/2022] [Indexed: 11/21/2022] Open
Abstract
Examples of isolated boron substituted nitroxide radicals are rare. The reaction of the reactive cyclic boraalkene 3 with nitrosobenzene yields a mixture of the [2 + 2] cycloaddition product 4a, the B-nitroxide radicals 5a and 6a and the azoxybenzene co-product 7avia a bora nitroso ene reaction pathway, the boron analogue of the nitroso ene reaction. The products were separated by flash chromatography, and the B-nitroxide radicals were characterized by X-ray diffraction and EPR spectroscopy. Radical 5a was shown to be a hydrogen atom abstractor. Both the B-nitroxide radicals are more easily oxidized compared to e.g. TEMPO, as shown by cyclic voltammetry. The NHC-stabilized boraalkene reacts with nitrosobenzene to give a [2+2] cycloaddition product plus a pair of persistent borylnitroxide radicals. These are thought to be formed by means of a bora nitroso ene reaction followed by H-atom transfer.![]()
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Affiliation(s)
- Chaohuang Chen
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Sina Klabunde
- Institut für Physikalische Chemie, Westfälische Wilhelms-Universität Münster Corrensstraße 28/3040 48149 Münster Germany
| | - Michael Ryan Hansen
- Institut für Physikalische Chemie, Westfälische Wilhelms-Universität Münster Corrensstraße 28/3040 48149 Münster Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
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22
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Zhang ZF, Yang MC, Su MD. Significant Insight into the Origin of Reaction Barriers Determining Dihydrogen Activation by G13-P-P (G13 = Group 13 Element) and G15-P-Ga (G15 = Group 15 Element) Frustrated Lewis Pairs. Inorg Chem 2021; 60:15253-15269. [PMID: 34570484 DOI: 10.1021/acs.inorgchem.1c01809] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The heterolytic cleavage of H2 by multiply bonded phosphorus-bridged G13-P-P-Rea (G13 = B, Al, Ga, In, and Tl) and G15-P-Ga-Rea (G15 = N, P, As, Sb, and Bi) frustrated Lewis pairs (FLPs) has been theoretically investigated using density functional theory calculations. For the above nine FLP-type molecules, our theoretical findings suggest that only Al-P-P-Rea, Ga-P-P-Rea, and In-P-P-Rea can undergo the energetically feasible H2 activation reaction from kinetic and thermodynamic viewpoints. Our study based on the activation strain model (ASM) reveals that gaining a better orbital overlap between G13-P-P-Rea and G15-P-Ga-Rea molecules and H2 affected the reaction barriers through the atomic radius of G13 and G15. According to our energy decomposition analysis-natural orbitals for chemical valence (EDA-NOCV) results, the bonding of these H2 activation reactions involving G13-P-P-Rea and G15-P-Ga-Rea is dominated by the donor-acceptor interaction (singlet-singlet interaction) rather than the electron-sharing interaction (triplet-triplet interaction). Moreover, our EDA-NOCV evidence reveals that the best description for the above bonding situations is the lone pair(G15) → σ*(H2) interaction rather than the empty p-π-orbital(G13) ← σ(H2) interaction. In particular, the findings in this work based on theoretically calculated geometries and the corresponding relative free energies of the stationary points combined with the results from the above sophisticated methods nicely agree with the famous Hammond postulate.
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Affiliation(s)
- Zheng-Feng Zhang
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Ming-Chung Yang
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Ming-Der Su
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan.,Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
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23
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Chen C, Daniliuc CG, Kehr G, Erker G. Formation and Cycloaddition Reactions of a Reactive Boraalkene Stabilized Internally by N-Heterocyclic Carbene. Angew Chem Int Ed Engl 2021; 60:19905-19911. [PMID: 34219331 DOI: 10.1002/anie.202106724] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/28/2021] [Indexed: 01/07/2023]
Abstract
The synthesis of element-carbon double bonds is of great importance for the development and understanding of reactive π-bonded systems in chemistry. The seven-membered heterocyclic system 4 b is readily made by internal C-H activation at a pendent isopropyl methyl group of the respective [(IPr)C6 F5 BH]+ borenium ion. Subsequent deprotonation with the IMes carbene gives the neutral cyclic boraalkene system 5 b. The B=C double bond in compound 5 b adds carbon dioxide, CS2 , sulfur dioxide, phenyl isocyanate, an acetylenic ester or two NO molecules to give the corresponding four-membered ring annulated heterocycles. With sulfur or selenium 5 b gives the respective three-membered ring systems. N2 O reacts with 5 b to give a mixture of the related oxaborirane 18 and a unique [B]OH containing diazoalkane product 19.
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Affiliation(s)
- Chaohuang Chen
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
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24
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Chen C, Daniliuc CG, Kehr G, Erker G. Formation and Cycloaddition Reactions of a Reactive Boraalkene Stabilized Internally by
N
‐Heterocyclic Carbene. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106724] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Chaohuang Chen
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
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25
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Mahaut D, Chardon A, Mineur L, Berionni G, Champagne B. Rational Development of a Metal-Free Bifunctional System for the C-H Activation of Methane: A Density Functional Theory Investigation. Chemphyschem 2021; 22:1958-1966. [PMID: 34309144 DOI: 10.1002/cphc.202100527] [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: 07/13/2021] [Indexed: 11/10/2022]
Abstract
The activation or heterolytic splitting of methane, a challenging substrate usually restricted to transition metals, has so far proven elusive in experimental frustrated Lewis pair (FLP) chemistry. In this article, we demonstrate, using density functional theory (DFT), that 1-aza-9-boratriptycene is a conceptually simple intramolecular FLP for the activation of methane. Systematic comparison with other FLP systems allows to gain insight into their reactivity with methane. The thermodynamics and kinetics of methane activation are interpreted by referring to the analysis of the natural charges and by employing the distortion-interaction/activation strain (DIAS) model. These showed that the nature of the Lewis base influences the selectivity over the reaction pathway, with N Lewis bases favoring the deprotonation mechanism and P bases the hydride abstraction one. The lower barrier of activation for 1-aza-9-boratriptycene and the higher products stability are due to a better interaction energy than its counterparts, itself due to electrostatic interactions with the methane moiety, favorable orbital overlaps allowed by the side-attack, and space proximity between the B and N atoms.
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Affiliation(s)
- Damien Mahaut
- Department of Chemistry, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles 61, B-5000, Namur, Belgium
| | - Aurélien Chardon
- Department of Chemistry, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles 61, B-5000, Namur, Belgium
| | - Loïc Mineur
- Department of Chemistry, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles 61, B-5000, Namur, Belgium
| | - Guillaume Berionni
- Department of Chemistry, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles 61, B-5000, Namur, Belgium
| | - Benoît Champagne
- Department of Chemistry, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles 61, B-5000, Namur, Belgium
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26
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Mondal H, Ghara M, Chattaraj PK. A computational investigation of the activation of allene (H2C = C = CHR; R = H, CH3, CN) by a frustrated phosphorous/boron Lewis pair. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2021.138623] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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27
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Marques LR, Ando RA. Probing the Charge Transfer in a Frustrated Lewis Pair by Resonance Raman Spectroscopy and DFT Calculations. Chemphyschem 2021; 22:522-525. [PMID: 33512751 DOI: 10.1002/cphc.202001024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/28/2021] [Indexed: 01/01/2023]
Abstract
A classical Lewis adduct derives from a covalent bond between a Lewis acid and a base. When the adduct formation is precluded by means of steric hindrance the association of the respective acid-base molecular system is defined as a frustrated Lewis pair (FLP). In this work, the archetypal FLP Mes3 P/B(C6 F5 )3 was characterized for the first time by resonance Raman spectroscopy, and the results were supported by density functional theory (DFT) calculations. The charge transfer nature of the lowest energy electronic transition, from phosphine to borane, was confirmed by the selective enhancement of the Raman bands associated to the FLP chromophore at resonance condition. Herein, we demonstrate the use of resonance Raman spectroscopy as a distinguished technique to probe the weak interaction involved in FLP chemistry.
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Affiliation(s)
- Leandro Ramos Marques
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes, 748, Butantã, 05508-000, São Paulo-SP, Brazil
| | - Rômulo Augusto Ando
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes, 748, Butantã, 05508-000, São Paulo-SP, Brazil
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28
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Dasgupta A, Richards E, Melen RL. Frustrated Radical Pairs: Insights from EPR Spectroscopy. Angew Chem Int Ed Engl 2021; 60:53-65. [PMID: 32931604 PMCID: PMC7883636 DOI: 10.1002/anie.202010633] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Indexed: 12/29/2022]
Abstract
Progress in frustrated Lewis pair (FLP) chemistry has revealed the importance of the main group elements in catalysis, opening new avenues in synthetic chemistry. Recently, new reactivities of frustrated Lewis pairs have been uncovered that disclose that certain combinations of Lewis acids and bases undergo single-electron transfer (SET) processes. Here an electron can be transferred from the Lewis basic donor to a Lewis acidic acceptor to generate a reactive frustrated radical pair (FRP). This minireview aims to showcase the recent advancements in this emerging field covering the synthesis and reactivities of frustrated radical pairs, with extensive highlights of the results from Electron Paramagnetic Resonance (EPR) spectroscopy to explain the nature and stability of the different radical species observed.
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Affiliation(s)
- Ayan Dasgupta
- School of ChemistryCardiff Catalysis InstituteCardiff UniversityMain Building, Park PlaceCardiffCF10 3ATUK
| | - Emma Richards
- School of ChemistryCardiff Catalysis InstituteCardiff UniversityMain Building, Park PlaceCardiffCF10 3ATUK
| | - Rebecca L. Melen
- School of ChemistryCardiff Catalysis InstituteCardiff UniversityMain Building, Park PlaceCardiffCF10 3ATUK
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29
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Sun Q, Daniliuc CG, Kehr G, Erker G. Reaction of carbon oxides with an ethylene-bridged PH/B Lewis pair. Dalton Trans 2021; 50:3523-3528. [PMID: 33599654 DOI: 10.1039/d1dt00459j] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of 2,4,6-tri(tert-butyl)phenyl vinyl phosphane with Piers' borane [HB(C6F5)2] gave the ethylene-bridged PH/B frustrated Lewis pair (FLP) system. It is a monomer at high temperature (>323 K), but exists as an associated 12-membered macrocyclic trimer below 273 K. The PH/B FLP splits dihydrogen and serves as a metal-free hydrogenation catalyst. It adds carbon dioxide. It serves as a PH/B template for the reduction of carbon monoxide by the HB(C6F5)2 borane to the formyl stage. The resulting six membered P/B/O containing heterocycle is opened upon treatment with pyridine and it reacts with benzaldehyde in a boron mediated Claisen-Tishchenko reaction.
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Affiliation(s)
- Qiu Sun
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
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30
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Zhang J, Xie Z. Tri-insertion with dearomatization of terminal arylalkynes using a carborane based frustrated Lewis pair template. Chem Sci 2020; 12:1745-1749. [PMID: 34163934 PMCID: PMC8179331 DOI: 10.1039/d0sc05755j] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 11/27/2020] [Indexed: 01/12/2023] Open
Abstract
Intramolecular vicinal Frustrated Lewis Pairs (FLPs) have played a significant role in the activation of small molecules, and their stabilities and reactivities are found to strongly depend on the nature of the bridging units. This work reports a new carborane based FLP, 1-PPh2-2-BPh2-1,2-C2B10H10 (2), which reacts with an equimolar amount of p-R2NC6H4C[triple bond, length as m-dash]CH (R = Me, Et, Ph) at room temperature to give C[triple bond, length as m-dash]C triple bond addition products 1,2-[PPh2C(R2NC6H4)[double bond, length as m-dash]CHBPh2]-1,2-C2B10H10 (3) in high yields. Compounds 3 react further with two equiv. of p-R2NC6H4C[triple bond, length as m-dash]CH (R = Me, Et) at 60-70 °C to give unprecedented stereoselective tri-insertion products, 3,3a,6,6a-tetrahydronaphtho[1,8a-b]borole tricycles (4), in which one of the aryl rings from arylacetylene moieties has been dearomatized with the formation of four stereocenters including one quaternary carbon center. It is noted that the phosphine unit functions as a catalyst during the reactions. After trapping and structural characterization of a key intermediate, a reaction mechanism is proposed, involving sequential alkyne insertion and 1,2-boryl migration.
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Affiliation(s)
- Jian Zhang
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong Shatin New Territories Hong Kong China
| | - Zuowei Xie
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong Shatin New Territories Hong Kong China
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31
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Can a decrease in anti-aromaticity increase the dihydrogen activation ability of a frustrated phosphorous/borane Lewis pair?: a DFT study. Theor Chem Acc 2020. [DOI: 10.1007/s00214-020-02698-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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32
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Dasgupta A, Richards E, Melen RL. Frustrated Radical Pairs: Insights from EPR Spectroscopy. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202010633] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Ayan Dasgupta
- School of Chemistry Cardiff Catalysis Institute Cardiff University Main Building, Park Place Cardiff CF10 3AT UK
| | - Emma Richards
- School of Chemistry Cardiff Catalysis Institute Cardiff University Main Building, Park Place Cardiff CF10 3AT UK
| | - Rebecca L. Melen
- School of Chemistry Cardiff Catalysis Institute Cardiff University Main Building, Park Place Cardiff CF10 3AT UK
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33
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Ghara M, Chattaraj PK. Noble Gas Binding Ability of an Au(I) Cation Stabilized by a Frustrated Lewis Pair: A DFT Study. Front Chem 2020; 8:616. [PMID: 32850643 PMCID: PMC7396548 DOI: 10.3389/fchem.2020.00616] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 06/11/2020] [Indexed: 11/23/2022] Open
Abstract
The noble gas (Ng) binding ability of a monocationic [(FLP)Au]+ species has been investigated by a computational study. Here, the monocationic [(FLP)Au]+ species is formed by coordination of Au(I) cation with the phosphorous (Lewis base) and the boron (Lewis acid) centers of a frustrated Lewis pair (FLP). The bonds involving Au and P, and Au and B atoms in [(FLP)Au]+ are partially covalent in nature as revealed by Wiberg bond index (WBI) values, electron density analysis and energy decomposition analysis (EDA). The zero point energy corrected bond dissociation energy (D0), enthalpy and free energy changes are computed for the dissociation of Au-Ng bonds to assess the Ng binding ability of [(FLP)Au]+ species. The D0 ranges from 6.0 to 13.3 kcal/mol, which increases from Ar to Rn. Moreover, the dissociation of Au-Ng bonds is endothermic as well as endergonic for Ng = Kr-Rn, whereas the same for Ng = Ar is endothermic but exergonic at room temperature. The partial covalent character of the bonds between Au and Ng atoms is demonstrated by their WBI values and electron density analysis. The Ng atoms get slight positive charges of 0.11–0.23 |e|, which indicates some amount of charge transfer takes place from it. EDA demonstrates that electrostatic and orbital interactions have equal contributions to stabilize the Ng-Au bonds in the [(FLP)AuNg]+ complex.
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Affiliation(s)
- Manas Ghara
- Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur, India
| | - Pratim Kumar Chattaraj
- Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur, India.,Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, India
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34
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Andrews RJ, Stephan DW. Isolable Anionic, Neutral and Cationic Radicals from Reactions of N,N'-Dimesityldiamidocarbene and Lewis Acids. Chemistry 2020; 26:7194-7198. [PMID: 32149432 DOI: 10.1002/chem.202001191] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Indexed: 01/04/2023]
Abstract
B(C6 F5 )3 undergoes nucleophilic attack by N,N'-dimesityldiamidocarbene (DAC) with fluoride transfer to the boron center, resulting in a new zwitterion (1). This B-F fluoride can be replaced or abstracted to give the corresponding hydride (2) or triflate (3) derivatives or the corresponding cation (4). These species are reduced with KC8 or Cp2 Co to give isolable anionic and neutral radicals (5-8). Similarly, the [Ph3 C] cation undergoes nucleophilic attack by DAC resulting in the spontaneous formation of the radical cation (9).
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Affiliation(s)
- Ryan J Andrews
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H4, Canada
| | - Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H4, Canada
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35
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Li J, Mück-Lichtenfeld C, Daniliuc CG, Kehr G, Erker G. Using the Secondary PH/BH Functional Groups of an Active Geminal Frustrated Lewis Pair for Carbon Monoxide Reduction and Reactions with Nitriles and Isonitriles. Angew Chem Int Ed Engl 2020; 59:12477-12483. [PMID: 31994804 DOI: 10.1002/anie.202000612] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Indexed: 11/10/2022]
Abstract
Reaction of the secondary alkynyl(Mes*)PH phosphane 2 with (Fmes)BH2 ⋅SMe2 gives the geminal PH/BH frustrated Lewis pair (FLP) 3. The PH and the BH functions are jointly used in the reduction of carbon monoxide under mild reaction conditions to give the [P]-CH2 -O-[B] product. A subsequent cycloaddition sequence results in the liberation of formaldehyde. The FLP 3 reacts with benzonitrile to give a P-benzamidine, and it couples two isonitriles at the FLP framework.
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Affiliation(s)
- Jun Li
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Christian Mück-Lichtenfeld
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany
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36
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Li J, Mück‐Lichtenfeld C, Daniliuc CG, Kehr G, Erker G. Using the Secondary PH/BH Functional Groups of an Active Geminal Frustrated Lewis Pair for Carbon Monoxide Reduction and Reactions with Nitriles and Isonitriles. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202000612] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Jun Li
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Christian Mück‐Lichtenfeld
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
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37
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Ghara M, Giri S, Chattaraj PK. Cycloaddition Reactions between H2C = CHR (R = H, CN, CH3) and a Cyclic P/B Frustrated Lewis Pair: A DFT Study. J Phys Chem A 2020; 124:4455-4462. [DOI: 10.1021/acs.jpca.0c02799] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Manas Ghara
- Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Santanab Giri
- Department of Applied Sciences and Humanities, Haldia Institute of Technology, Haldia 721657, India
| | - Pratim Kumar Chattaraj
- Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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38
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Zhang H, Zhan XY, Dong Y, Yang J, He S, Shi ZC, Zhang XM, Wang JY. Dehydration in water: frustrated Lewis pairs directly catalyzed allylization of electron-rich arenes and allyl alcohols. RSC Adv 2020; 10:16942-16948. [PMID: 35521451 PMCID: PMC9053410 DOI: 10.1039/d0ra02912b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 04/23/2020] [Indexed: 01/23/2023] Open
Abstract
A frustrated Lewis pair (FLP)-catalyzed allylation of allyl alcohols with electron-rich arenes has been developed. Interestingly, in this reaction, the electron-rich arenes and allyl alcohols are dehydrated in water. What's more, water was the sole byproduct of the reaction. In this protocol, various allyl alcohols can be converted into allyl cations and attacked by the electron-rich arenes to form aryl cation intermediates. Finally, the aryl cation intermediates are deprotonated to give the 1,3-diarylpropenes. In this protocol, indole allyl alcohols can undergo a bimolecular ring closure reaction, and structurally diverse tetrahydroindolo[3,2-b]carbazoles could be smoothly obtained. The reaction is not sensitive to oxygen and has been performed on a gram-scale.
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Affiliation(s)
- Hua Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Xiao-Yu Zhan
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Yu Dong
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Jian Yang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Shuai He
- Southwest Minzu University Chengdu 610041 P. R. China
| | - Zhi-Chuan Shi
- Southwest Minzu University Chengdu 610041 P. R. China
| | - Xiao-Mei Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 P. R. China
| | - Ji-Yu Wang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 P. R. China
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39
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Affiliation(s)
- Wei Meng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences Beijing 100049 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Xiangqing Feng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences Beijing 100049 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Haifeng Du
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences Beijing 100049 China
- University of Chinese Academy of Sciences Beijing 100049 China
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40
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Sun X, Su W, Shi K, Xie Z, Zhu C. Triple Frustrated Lewis Pair-Type Reactivity on a Single Rare-Earth Metal Center. Chemistry 2020; 26:5354-5359. [PMID: 31950533 DOI: 10.1002/chem.201905629] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Indexed: 12/28/2022]
Abstract
Rare-earth metal cations have been used rarely as Lewis-acidic components in the chemistry of frustrated Lewis pairs (FLPs). Herein, we report the first cerium/phosphorus system (2) employing a heptadentate N4 P3 ligand, which exhibits triple FLP-type reactivity towards a series of organic substrates, including isocyanates, isothiocyanates, diazomethane, and azides on a single rare-earth Lewis acidic Ce center. This result shows that the Ce center and three P atoms in 2 could simultaneously activate three equivalents of small molecules under mild conditions. This study broadens the diversity of FLPs and demonstrates that rare earth based FLP exhibit unique properties compared with other FLP systems.
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Affiliation(s)
- Xiong Sun
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
| | - Wei Su
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
| | - Kaiying Shi
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
| | - Zhuoyi Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
| | - Congqing Zhu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
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41
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Hong M, Wu S, Li J, Wang J, Wei L, Li K. Aerobic oxidation of 5-(hydroxymethyl)furfural into 2,5-diformylfuran catalyzed by starch supported aluminum nitrate. CATAL COMMUN 2020. [DOI: 10.1016/j.catcom.2019.105909] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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42
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Gallardo-Fuentes S, Ormazábal-Toledo R. Theoretical insights into the activation of N2O by a model Frustrated Lewis Pair. An ab-initio metadynamics study. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2019.137002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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43
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Jie X, Sun Q, Daniliuc CG, Knitsch R, Hansen MR, Eckert H, Kehr G, Erker G. Cycloaddition Reactions of an Active Cyclic Phosphane/Borane Pair with Alkenes, Alkynes, and Carbon Dioxide. Chemistry 2020; 26:1269-1273. [DOI: 10.1002/chem.201905171] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Indexed: 11/05/2022]
Affiliation(s)
- Xiaoming Jie
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Qiu Sun
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Robert Knitsch
- Institut für Physikalische ChemieWestfälische Wilhelms-Universität, Münster Corrensstraße 28 48149 Münster Germany
| | - Michael Ryan Hansen
- Institut für Physikalische ChemieWestfälische Wilhelms-Universität, Münster Corrensstraße 28 48149 Münster Germany
| | - Hellmut Eckert
- Institut für Physikalische ChemieWestfälische Wilhelms-Universität, Münster Corrensstraße 28 48149 Münster Germany
- Instituto de Fisica, Sáo CarlosUniversidade de São Paulo CP 369 13566-590 São Carlos S. P. Brazil
| | - Gerald Kehr
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Gerhard Erker
- Organisch-Chemisches InstitutWestfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
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44
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Patrick EA, Piers WE. Twenty-five years of bis-pentafluorophenyl borane: a versatile reagent for catalyst and materials synthesis. Chem Commun (Camb) 2020; 56:841-853. [DOI: 10.1039/c9cc08338c] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Highlights of the extensive chemistry and applications of bis-pentafluorophenyl borane (“Piers’ borane”) from the 25 years since its first appearance are featured.
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45
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Sun X, Zhu Q, Xie Z, Su W, Zhu J, Zhu C. An Unprecedented Ga/P Frustrated Lewis Pair: Synthesis, Characterization, and Reactivity. Chemistry 2019; 25:14295-14299. [DOI: 10.1002/chem.201904081] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Indexed: 11/11/2022]
Affiliation(s)
- Xiong Sun
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
| | - Qin Zhu
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), andDepartment of ChemistryCollege of Chemistry, and Chemical EngineeringXiamen University Xiamen 361005 P. R. China
| | - Zhuoyi Xie
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
| | - Wei Su
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
| | - Jun Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), andDepartment of ChemistryCollege of Chemistry, and Chemical EngineeringXiamen University Xiamen 361005 P. R. China
| | - Congqing Zhu
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 P. R. China
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46
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Hong M, Min J, Wu S, Cui H, Zhao Y, Li J, Wang S. Metal Nitrate Catalysis for Selective Oxidation of 5-Hydroxymethylfurfural into 2,5-Diformylfuran under Oxygen Atmosphere. ACS OMEGA 2019; 4:7054-7060. [PMID: 31459816 PMCID: PMC6648045 DOI: 10.1021/acsomega.9b00391] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 04/11/2019] [Indexed: 05/26/2023]
Abstract
Selective synthesis of various versatile compounds from biomass is of great importance to displace traditional fossil fuel resources. Here, homogeneous metal nitrate (M(NO3) x )/(2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) and M(NO3) x /TEMPO/NaNO2 catalyst systems in glacial acetic acid and acetonitrile, respectively, have been found to be highly active and practically sustainable for selective oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-diformylfuran (DFF) using pure O2 or even O2 in air as the oxidant. The catalytic methods enable full HMF conversion with a nearly 100% DFF selectivity at 50 °C under atmospheric pressure using a very simple reaction setup and workup. Mechanistic aspects are discussed. The influences of reaction conditions such as different metal catalysts, catalyst loading, solvents, and reaction temperature on the promotion effect were studied. Meanwhile, the catalyst systems had also good performance for aerobic oxidation of other alcohols.
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Affiliation(s)
- Mei Hong
- Jiangsu
Co-Innovation Center of Efficient Processing and Utilization
of Forest Resources and College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People’s Republic of China
| | - Jie Min
- Jiangsu
Co-Innovation Center of Efficient Processing and Utilization
of Forest Resources and College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People’s Republic of China
| | - Shuangyan Wu
- Jiangsu
Co-Innovation Center of Efficient Processing and Utilization
of Forest Resources and College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People’s Republic of China
| | - Huangui Cui
- Jiangsu
Co-Innovation Center of Efficient Processing and Utilization
of Forest Resources and College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People’s Republic of China
| | - Yuxin Zhao
- Jiangsu
Co-Innovation Center of Efficient Processing and Utilization
of Forest Resources and College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People’s Republic of China
| | - Jiatong Li
- Jiangsu
Co-Innovation Center of Efficient Processing and Utilization
of Forest Resources and College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People’s Republic of China
| | - Shifa Wang
- Jiangsu
Co-Innovation Center of Efficient Processing and Utilization
of Forest Resources and College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People’s Republic of China
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47
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Ghara M, Chattaraj PK. A computational study on hydrogenation of CO2, catalyzed by a bridged B/N frustrated Lewis pair. Struct Chem 2019. [DOI: 10.1007/s11224-018-1264-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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48
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Abstract
While conventional approaches to stabilizing main group radicals have involved the use of Lewis acids or bases, this tutorial review focuses on new avenues to main group radicals derived from combinations of donor and acceptor molecules.
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Affiliation(s)
- Liu Leo Liu
- Department of Chemistry
- University of Toronto
- Toronto
- Canada
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49
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Ghara M, Pan S, Chattaraj PK. A theoretical investigation on boron–ligand cooperation to activate molecular hydrogen by a frustrated Lewis pair and subsequent reduction of carbon dioxide. Phys Chem Chem Phys 2019; 21:21267-21277. [DOI: 10.1039/c9cp03756j] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Activation of molecular hydrogen by a B/N frustrated Lewis pair.
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Affiliation(s)
- Manas Ghara
- Department of Chemistry and Center for Theoretical Studies
- Indian Institute of Technology Kharagpur
- Kharagpur-721302
- India
| | - Sudip Pan
- Fachbereich Chemie
- Philipps-Universität Marburg Hans-Meerwein-Straße
- 35032 Marburg
- Germany
| | - Pratim K. Chattaraj
- Department of Chemistry and Center for Theoretical Studies
- Indian Institute of Technology Kharagpur
- Kharagpur-721302
- India
- Department of Chemistry
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50
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Rational design of FLP catalysts for reversible H2 activation: A DFT study of the geometric and electronic effects. CHINESE CHEM LETT 2018. [DOI: 10.1016/j.cclet.2018.02.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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