1
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Laglera-Gándara CJ, Jiménez-Pérez J, Fernández-de-Córdova FJ, Ríos P, Conejero S. Electrophilic Hydrosilylation of Electron-Rich Alkenes Derived from Enamines. Angew Chem Int Ed Engl 2024; 63:e202404859. [PMID: 38634763 DOI: 10.1002/anie.202404859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/16/2024] [Accepted: 04/16/2024] [Indexed: 04/19/2024]
Abstract
The low-electron count, air-stable, platinum complexes [Pt(ItBu')(ItBu)][BArF] (C1) (ItBu=1,3-di-tert-butylimidazol-2-ylidene), [Pt(SiPh)3(ItBuiPr)2][BArF] (C2) (ItBuiPr=1-tert-butyl-3-iso-propylimidazol-2-ylidene), [Pt(SiPh)3(ItBuMe)2][BArF] (C3), [Pt(GePh3)(ItBuiPr)2][BArF] (C4), [Pt(GePh)3(ItBuMe)2][BArF] (C5) and [Pt(GeEt)3(ItBuMe)2][BArF] (C6) (ItBuMe=1-tert-butyl-3-methylimidazol-2-ylidene) are efficient catalysts (particularly the germyl derivatives) in both the silylative dehydrocoupling and hydrosilylation of electron rich alkenes derived from enamines. The steric hindrance exerted by the NHC ligand plays an important role in the selectivity of the reaction. Thus, bulky ligands are selective towards the silylative dehydrocoupling process whereas less sterically hindered promote the selective hydrosilylation reaction. The latter is, in addition, regioselective towards the β-carbon atom of both internal and terminal enamines, leading to β-aminosilanes. Moreover, the syn stereochemistry of the amino and silyl groups implies an anti Si-H bond addition across the double bond. All these facts point to a mechanistic picture that, according to experimental and computational studies, involves a non-classical hydrosilylation process through an outer-sphere mechanism in which a formal nucleophilic addition of the enamine to the silicon atom of a platinum σ-SiH complex is the key step. This is in sharp contrast with the classical Chalk-Harrod mechanism prevalent in platinum chemistry.
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Affiliation(s)
- Carlos J Laglera-Gándara
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
| | - Julián Jiménez-Pérez
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
| | - Francisco J Fernández-de-Córdova
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
| | - Pablo Ríos
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
| | - Salvador Conejero
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), CSIC and Universidad de Sevilla, Avda. Américo Vespucio 49, 41092, Sevilla, Spain
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2
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Cao VD, Joung S. Synthesis and utility of N-boryl and N-silyl enamines derived from the hydroboration and hydrosilylation of N-heteroarenes and N-conjugated compounds. Front Chem 2024; 12:1414328. [PMID: 38911995 PMCID: PMC11190178 DOI: 10.3389/fchem.2024.1414328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 05/17/2024] [Indexed: 06/25/2024] Open
Abstract
Catalytic hydroboration and hydrosilylation have emerged as promising strategies for the reduction of unsaturated hydrocarbons and carbonyl compounds, as well as for the dearomatization of N-heteroarenes. Various catalysts have been employed in these processes to achieve the formation of reduced products via distinct reaction pathways and intermediates. Among these intermediates, N-silyl enamines and N-boryl enamines, which are derived from hydrosilylation and hydroboration, are commonly underestimated in this reduction process. Because these versatile intermediates have recently been utilized in situ as nucleophilic reagents or dipolarophiles for the synthesis of diverse molecules, an expeditious review of the synthesis and utilization of N-silyl and N-boryl enamines is crucial. In this review, we comprehensively discuss a wide range of hydrosilylation and hydroboration catalysts used for the synthesis of N-silyl and N-boryl enamines. These catalysts include main-group metals (e.g., Mg and Zn), transition metals (e.g., Rh, Ru, and Ir), earth-abundant metals (e.g., Fe, Co, and Ni), and non-metal catalysts (including P, B, and organocatalysts). Furthermore, we highlight recent research efforts that have leveraged these versatile intermediates for the synthesis of intriguing molecules, offering insights into future directions for these invaluable building blocks.
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Affiliation(s)
| | - Seewon Joung
- Department of Chemistry, Inha University, Incheon, Republic of Korea
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3
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Kumar R, Meher RK, Karmakar H, Panda TK. Hydrosilylation of nitriles and tertiary amides using a zinc precursor. Org Biomol Chem 2024; 22:3053-3058. [PMID: 38545870 DOI: 10.1039/d4ob00161c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2024]
Abstract
We report a competent and selective hydrosilylation of nitriles and tertiary amides catalyzed by the readily available zinc bis(hexamethyldisilazide) under solvent-free and mild conditions, making it a sustainable and desirable alternative to existing methods. Both protocols afforded high conversion, superior selectivity, and a broad substrate scope, from electron-withdrawing to electron-donating and heterocyclic substitutions.
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Affiliation(s)
- Ravi Kumar
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Rohan Kumar Meher
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Himadri Karmakar
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Tarun K Panda
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
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4
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Kong RY, Parry JB, Anello GR, Ong ME, Lancaster KM. Accelerating σ-Bond Metathesis at Sn(II) Centers. J Am Chem Soc 2023; 145:24136-24144. [PMID: 37870565 DOI: 10.1021/jacs.3c07997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
Molecular main-group hydride catalysts are attractive as cheap and Earth-abundant alternatives to transition-metal analogues. In the case of the latter, specific steric and electronic tuning of the metal center through ligand choice has enabled the iterative and rational development of superior catalysts. Analogously, a deeper understanding of electronic structure-activity relationships for molecular main-group hydrides should facilitate the development of superior main-group hydride catalysts. Herein, we report a modular Sn-Ni bimetallic system in which we systematically vary the ancillary ligand on Ni, which, in turn, tunes the Sn center. This tuning is probed using Sn L1 XAS as a measure of electron density at the Sn center. We demonstrate that increased electron density at Sn centers accelerates the rate of σ-bond metathesis, and we employ this understanding to develop a highly active Sn-based catalyst for the hydroboration of CO2 using pinacolborane. Additionally, we demonstrate that engineering London dispersion interactions within the secondary coordination sphere of Sn allows for further rate acceleration. These results show that the electronics of main-group catalysts can be controlled without the competing effects of geometry perturbations and that this manifests in substantial reactivity differences.
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Affiliation(s)
- Richard Y Kong
- Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, 162 Sciences Drive, Ithaca, New York 14853, United States
| | - Joseph B Parry
- Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, 162 Sciences Drive, Ithaca, New York 14853, United States
| | - Guy R Anello
- Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, 162 Sciences Drive, Ithaca, New York 14853, United States
| | - Matthew E Ong
- Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, 162 Sciences Drive, Ithaca, New York 14853, United States
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, 162 Sciences Drive, Ithaca, New York 14853, United States
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5
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Radzhabov MR, Mankad NP. Activation of robust bonds by carbonyl complexes of Mn, Fe and Co. Chem Commun (Camb) 2023; 59:11932-11946. [PMID: 37727948 DOI: 10.1039/d3cc03078d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
Metal carbonyl complexes possess among the most storied histories of any compound class in organometallic chemistry. Nonetheless, these old dogs continue to be taught new tricks. In this Feature, we review the historic discoveries and recent advances in cleaving robust bonds (e.g., C-H, C-O, C-F) using carbonyl complexes of three metals: Mn, Fe, and Co. The use of Mn, Fe, and Co carbonyl catalysts in controlling selectivity during hydrofunctionalization reactions is also discussed. The chemistry of these earth-abundant metals in the field of robust bond functionalization is particularly relevant in the context of sustainability. We expect that an up-to-date perspective on these seemingly simple organometallic species will emphasize the wellspring of reactivity that continues to be available for discovery.
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Affiliation(s)
- Maxim R Radzhabov
- Department of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, USA.
| | - Neal P Mankad
- Department of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, USA.
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6
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Ramachandran PV, Hamann HJ. Dehydroborylation of Terminal Alkynes Using Lithium Aminoborohydrides. Molecules 2023; 28:molecules28083433. [PMID: 37110669 PMCID: PMC10144115 DOI: 10.3390/molecules28083433] [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: 03/22/2023] [Revised: 04/10/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Dehydrogenative borylation of terminal alkynes has recently emerged as an atom-economical one-step alternative to traditional alkyne borylation methodologies. Using lithium aminoborohydrides, formed in situ from the corresponding amine-boranes and n-butyllithium, a variety of aromatic and aliphatic terminal alkyne substrates were successfully borylated in high yield. The potential to form mono-, di-, and tri-B-alkynylated products has been shown, though the mono-product is primarily generated using the presented condition. The reaction has been demonstrated at large (up to 50 mmol) scale, and the products are stable to column chromatography as well as acidic and basic aqueous conditions. Alternately, the dehydroborylation can be achieved by treating alkynyllithiums with amine-boranes. In that respect, aldehydes can act as starting materials by conversion to the 1,1-dibromoolefin and in situ rearrangement to the lithium acetylide.
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Affiliation(s)
- P Veeraraghavan Ramachandran
- Herbert C. Brown Center for Borane Research, Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907, USA
| | - Henry J Hamann
- Herbert C. Brown Center for Borane Research, Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907, USA
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7
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Pan X, Talavera M, Braun T. Efficient hydrostannation of fluorinated alkenes. J Fluor Chem 2023. [DOI: 10.1016/j.jfluchem.2023.110116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
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8
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Shangin PG, Akyeva AY, Vakhrusheva DM, Minyaev ME, Mankaev BN, Balycheva VA, Lalov AV, Egorov MP, Karlov SS, Syroeshkin MA. The Role of Ligands in Oxidative Addition Chemistry of Low-Valent Main Group Derivatives: Not Only Stabilization but Also Activation. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Affiliation(s)
- Pavel G. Shangin
- Zelinsky Institute of Organic Chemistry RAS, Leninsky prospect 47, Moscow 119991, Russia
| | - Anna Ya. Akyeva
- Zelinsky Institute of Organic Chemistry RAS, Leninsky prospect 47, Moscow 119991, Russia
| | - Daria M. Vakhrusheva
- Zelinsky Institute of Organic Chemistry RAS, Leninsky prospect 47, Moscow 119991, Russia
| | - Mikhail E. Minyaev
- Zelinsky Institute of Organic Chemistry RAS, Leninsky prospect 47, Moscow 119991, Russia
| | - Badma N. Mankaev
- Lomonosov Moscow State University, B-234 Leninskie Gory, Moscow 119991, Russia
| | - Victoriya A. Balycheva
- Zelinsky Institute of Organic Chemistry RAS, Leninsky prospect 47, Moscow 119991, Russia
| | - Andrey V. Lalov
- Zelinsky Institute of Organic Chemistry RAS, Leninsky prospect 47, Moscow 119991, Russia
| | - Mikhail P. Egorov
- Zelinsky Institute of Organic Chemistry RAS, Leninsky prospect 47, Moscow 119991, Russia
| | - Sergey S. Karlov
- Lomonosov Moscow State University, B-234 Leninskie Gory, Moscow 119991, Russia
| | - Mikhail A. Syroeshkin
- Zelinsky Institute of Organic Chemistry RAS, Leninsky prospect 47, Moscow 119991, Russia
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9
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Li H, Yang C, Wang D, Deng L. Cobalt-Catalyzed Regio- and Stereoselective Hydrosilylation of Alk-2-ynes with Tertiary Silanes. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Hongfang Li
- College of Chemistry and Materials Science, Shanghai Normal University, Shanghai 200234, China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Chengbo Yang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Dongyang Wang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, 1 Sub-lane Xiangshan, Hangzhou 310024, China
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10
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Shi Y, Wang Y, Huang Z, Zhang F, Shao Y. t BuOLi-Promoted Hydroboration of Esters and Epoxides. ACS OMEGA 2022; 7:18876-18886. [PMID: 35694491 PMCID: PMC9178618 DOI: 10.1021/acsomega.2c01866] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
Commercially available and inexpensive lithium tert-butoxide ( t BuOLi) acts as a good precatalyst for the hydroboration of esters, lactones, and epoxides using pinacolborane as a borylation agent. Functional groups such as cyano-, nitro-, amino-, vinyl, and alkynyl are unaffected under the presented hydroboration process, representing high chemoselectivity. This transformation has also been effectively applied to the synthesis of key intermediates of Erlotinib and Cinacalcet. Preliminary investigations of the mechanism show that the hydroboration proceeds through the in situ formed BH3 species.
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Affiliation(s)
- Yinyin Shi
- College
of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Yue Wang
- College
of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Zhefan Huang
- College
of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Fangjun Zhang
- School
of Pharmaceutical Sciences, Wenzhou Medical
University, Wenzhou 325035, China
| | - Yinlin Shao
- College
of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China
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11
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Schorr F, Arrowsmith M, Fantuzzi F, Rempel A, Braunschweig H. 1,2-Dialkynyldiboranes(4): B-B versus CC bond reactivity. Dalton Trans 2022; 51:6197-6203. [PMID: 35388860 DOI: 10.1039/d2dt00683a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactivity of three 1,2-dialkynyl-1,2-diaminodiborane(4) derivatives, B2(NMe2)2(CCR)2 (R = H, Me, SiMe3), towards small molecules known to react with both B-B and CC bonds was studied. With arylazides nitrene insertion into the B-B bond with concomitant loss of N2 was kinetically favoured in all cases. While reactions with sterically unhindered hydroboranes proceeded unselectively, sterically encumbered dimesitylborane cleanly added to both alkynyl moieties, resulting in the first examples of 1,2-divinyldiboranes(4). In the presence of catalytic amounts of Pd/C room-temperature hydrogenation at 1 bar led to oxidative B-B bond cleavage and yielded the fully hydrogenated alkyl(amino)hydroborane products. These could be prevented from dimerising and isolated by complexation with an NHC ligand. Finally, stepwise halogenation of the B-B bond and the alkynyl groups afforded first the corresponding alkynyl(amino)haloboranes and then the amino(halo)(1,2-dihalovinyl)boranes.
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Affiliation(s)
- Fabian Schorr
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. .,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. .,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Felipe Fantuzzi
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. .,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Physical and Theoretical Chemistry, Julius-Maximilians-Universität Würzburg, Emil-Fischer-Str. 42, 97074 Würzburg, Germany.,School of Physical Sciences, Ingram Building, University of Kent, Park Wood Rd, Canterbury CT2 7NH, UK
| | - Anna Rempel
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. .,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. .,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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12
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Dahiya A, Schoenebeck F. Direct C-H Dehydrogenative Germylation of Terminal Alkynes with Hydrogermanes. Org Lett 2022; 24:2728-2732. [PMID: 35364815 DOI: 10.1021/acs.orglett.2c00840] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A direct C(sp)-H germylation of terminal alkynes with triethyl germanium hydride is reported. The method is operationally simple and makes use of B(C6F5)3 catalysis in combination with 2,6-lutidine as an organic base. Exclusive selectivity for dehydrogenative germylation of the alkyne over the competing hydrogermylation is observed.
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Affiliation(s)
- Amit Dahiya
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
| | - Franziska Schoenebeck
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
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13
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Abstract
The addition of a B-H bond to an unsaturated bond (polarized or unpolarized) is a powerful and atom-economic tool for the synthesis of organoboranes. In recent years, s-block organometallics have appeared as alternative catalysts to transition-metal complexes, which traditionally catalyze the hydroboration of unsaturated bonds. Because of the recent and rapid development in the field of hydroboration of unsaturated bonds catalyzed by alkali (Li, Na, K) and alkaline earth (Mg, Ca, Sr, Ba) metals, we provide a detailed and updated comprehensive review that covers the synthesis, reactivity, and application of s-block metal catalysts in the hydroboration of polarized as well as unsaturated carbon-carbon bonds. Moreover, we describe the main reaction mechanisms, providing valuable insight into the reactivity of the s-block metal catalysts. Finally, we compare these s-block metal complexes with other redox-neutral catalytic systems based on p-block metals including aluminum complexes and f-block metal complexes of lanthanides and early actinides. In this review, we aim to provide a comprehensive, authoritative, and critical assessment of the state of the art within this highly interesting research area.
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Affiliation(s)
- Marc Magre
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
| | - Marcin Szewczyk
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
| | - Magnus Rueping
- Chemical Science Program, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), KAUST Catalysis Center, Thuwal 23955-6900, Kingdom of Saudi Arabia
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14
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Marciniec B, Pietraszuk C, Pawluć P, Maciejewski H. Inorganometallics (Transition Metal-Metalloid Complexes) and Catalysis. Chem Rev 2021; 122:3996-4090. [PMID: 34967210 PMCID: PMC8832401 DOI: 10.1021/acs.chemrev.1c00417] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
While the formation
and breaking of transition metal (TM)–carbon
bonds plays a pivotal role in the catalysis of organic compounds,
the reactivity of inorganometallic species, that is, those involving
the transition metal (TM)–metalloid (E) bond, is of key importance
in most conversions of metalloid derivatives catalyzed by TM complexes.
This Review presents the background of inorganometallic catalysis
and its development over the last 15 years. The results of mechanistic
studies presented in the Review are related to the occurrence of TM–E
and TM–H compounds as reactive intermediates in the catalytic
transformations of selected metalloids (E = B, Si, Ge, Sn, As, Sb,
or Te). The Review illustrates the significance of inorganometallics
in catalysis of the following processes: addition of metalloid–hydrogen
and metalloid–metalloid bonds to unsaturated compounds; activation
and functionalization of C–H bonds and C–X bonds with
hydrometalloids and bismetalloids; activation and functionalization
of C–H bonds with vinylmetalloids, metalloid halides, and sulfonates;
and dehydrocoupling of hydrometalloids. This first Review on inorganometallic
catalysis sums up the developments in the catalytic methods for the
synthesis of organometalloid compounds and their applications in advanced
organic synthesis as a part of tandem reactions.
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Affiliation(s)
- Bogdan Marciniec
- Faculty of Chemistry, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland.,Center for Advanced Technology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 10, 61-614 Poznań, Poland
| | - Cezary Pietraszuk
- Faculty of Chemistry, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland
| | - Piotr Pawluć
- Faculty of Chemistry, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland.,Center for Advanced Technology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 10, 61-614 Poznań, Poland
| | - Hieronim Maciejewski
- Faculty of Chemistry, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland
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15
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Park JW. Cobalt-catalyzed alkyne hydrosilylation as a new frontier to selectively access silyl-hydrocarbons. Chem Commun (Camb) 2021; 58:491-504. [PMID: 34889931 DOI: 10.1039/d1cc06214j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The hydrosilylation of alkynes is a chief chemical method for accessing a range of alkenylsilanes, which can be derivatized to obtain value-added hydrocarbons and utilized in diverse applications. While noble metal-based catalytic procedures have shown great success in accessing vinylsilanes within the context of both academia and industry, replacing the noble metals with cheaper and more abundant base metals has recently drawn significant interest due to their catalytic sustainability and competencies including unprecedented reactivity that could expand chemical tools for accessing other types of silicon-containing hydrocarbons. During the past few years, a number of well-defined, robust cobalt-catalyst platforms that broadly operate either the Chalk-Harrod or a modified Chalk-Harrod mechanism have emerged as a new frontier in the field of selective alkyne hydrosilylation. This review describes the main features of cobalt catalyst systems recently documented for the hydrosilylation of alkynes with a strong emphasis on ligand design and reaction pathways involving Co-H and/or Co-silyl species-mediated elementary transformations to achieve Markovnikov/anti-Markovnikov hydrosilylations as well as new migratory transformations.
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Affiliation(s)
- Jung-Woo Park
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea.,Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
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16
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Qin F, Wang H, Cao T, Liu Q, Xu Q, Zheng H, Zhu M, Li T, Liu Y, Wei W. Metal‐free Radical Cyclization of Olefinic 1,3‐Dicarbonyls and Olefinic Amides with Nitrile C(sp
3
)−H Bonds in Aqueous Media. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Fu‐Hua Qin
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products School of Materials Science and Chemical Engineering Ningbo University Ningbo, Zhejiang 315211 P. R. China
| | - Hui‐Zhi Wang
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products School of Materials Science and Chemical Engineering Ningbo University Ningbo, Zhejiang 315211 P. R. China
| | - Ting‐Ting Cao
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products School of Materials Science and Chemical Engineering Ningbo University Ningbo, Zhejiang 315211 P. R. China
| | - Qi‐Li Liu
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products School of Materials Science and Chemical Engineering Ningbo University Ningbo, Zhejiang 315211 P. R. China
| | - Qing Xu
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products School of Materials Science and Chemical Engineering Ningbo University Ningbo, Zhejiang 315211 P. R. China
| | - Hongxing Zheng
- Institution of Functional Organic Molecules and Materials School of Chemistry and Chemical Engineering Liaocheng University Liaocheng, Shandong 252059 P. R. China
| | - Meiling Zhu
- College of Chemistry and Pharmaceutical Engineering Nanyang Normal University Nanyang, Henan 473061 P. R. China
| | - Ting Li
- College of Chemistry and Pharmaceutical Engineering Nanyang Normal University Nanyang, Henan 473061 P. R. China
| | - Yi‐Lin Liu
- College of Chemistry and Materials Engineering Hunan Engineering Laboratory for Preparation Technology of Polyvinyl Alcohol (PVA) Fiber Material Huaihua University Huaihua, Hunan 418008 P. R. China
| | - Wen‐Ting Wei
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products School of Materials Science and Chemical Engineering Ningbo University Ningbo, Zhejiang 315211 P. R. China
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17
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González MJ, Bauer F, Breit B. Cobalt-Catalyzed Hydroboration of Terminal and Internal Alkynes. Org Lett 2021; 23:8199-8203. [PMID: 34618449 DOI: 10.1021/acs.orglett.1c02854] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel methodology to access synthetically versatile vinylboronic esters through a ligand-controlled cobalt-catalyzed hydroboration of terminal and internal alkynes is reported. The approach relies on the in situ reduction of Co(II) by H-BPin in the presence of bisphosphine ligands generating catalytically active Co(I) hydride complexes. This procedure avoids the use of stoichiometric amounts of base, and no boron-containing byproducts are generated which is translated into high functional group tolerance and atom economy.
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Affiliation(s)
- María J González
- Institut für Organische Chemie, Albert-Ludwigs-Universität 21, 79104 Freiburg, Germany
| | - Felix Bauer
- Institut für Organische Chemie, Albert-Ludwigs-Universität 21, 79104 Freiburg, Germany
| | - Bernhard Breit
- Institut für Organische Chemie, Albert-Ludwigs-Universität 21, 79104 Freiburg, Germany
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18
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Rej S, Das A, Panda TK. Overview of Regioselective and Stereoselective Catalytic Hydroboration of Alkynes. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202100950] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Supriya Rej
- Institut für Chemie Technische Universität Berlin Berlin, Strasse des 17. Juni 115 10623 Berlin Germany
| | - Amrita Das
- Department of Applied Chemistry Faculty of Engineering Osaka University 565-0871 Suita Osaka Japan
| | - Tarun K. Panda
- Department of Chemistry Indian Institute of Technology Hyderabad Kandi 502285 Sangareddy Telangana India
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19
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Neveselý T, Wienhold M, Molloy JJ, Gilmour R. Advances in the E → Z Isomerization of Alkenes Using Small Molecule Photocatalysts. Chem Rev 2021; 122:2650-2694. [PMID: 34449198 DOI: 10.1021/acs.chemrev.1c00324] [Citation(s) in RCA: 147] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Geometrical E → Z alkene isomerization is intimately entwined in the historical fabric of organic photochemistry and is enjoying a renaissance (Roth et al. Angew. Chem., Int. Ed. Engl. 1989 28, 1193-1207). This is a consequence of the fundamental stereochemical importance of Z-alkenes, juxtaposed with frustrations in thermal reactivity that are rooted in microscopic reversibility. Accessing excited state reactivity paradigms allow this latter obstacle to be circumnavigated by exploiting subtle differences in the photophysical behavior of the substrate and product chromophores: this provides a molecular basis for directionality. While direct irradiation is operationally simple, photosensitization via selective energy transfer enables augmentation of the alkene repertoire to include substrates that are not directly excited by photons. Through sustained innovation, an impressive portfolio of tailored small molecule catalysts with a range of triplet energies are now widely available to facilitate contra-thermodynamic and thermo-neutral isomerization reactions to generate Z-alkene fragments. This review is intended to serve as a practical guide covering the geometric isomerization of alkenes enabled by energy transfer catalysis from 2000 to 2020, and as a logical sequel to the excellent treatment by Dugave and Demange (Chem. Rev. 2003 103, 2475-2532). The mechanistic foundations underpinning isomerization selectivity are discussed together with induction models and rationales to explain the counterintuitive directionality of these processes in which very small energy differences distinguish substrate from product. Implications for subsequent stereospecific transformations, application in total synthesis, regioselective polyene isomerization, and spatiotemporal control of pre-existing alkene configuration in a broader sense are discussed.
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Affiliation(s)
- Tomáš Neveselý
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Max Wienhold
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - John J Molloy
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Ryan Gilmour
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Münster, Germany
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20
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Lai YL, Yan S, He D, Zhou LZ, Chen ZS, Du YL, Li J. Palladium-catalyzed bisthiolation of terminal alkynes for the assembly of diverse ( Z)-1,2-bis(arylthio)alkene derivatives. RSC Adv 2021; 11:28447-28451. [PMID: 35478536 PMCID: PMC9037987 DOI: 10.1039/d1ra05773a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 08/18/2021] [Indexed: 01/19/2023] Open
Abstract
An efficient and straightforward palladium-catalyzed three-component cascade bisthiolation of terminal alkynes and arylhydrazines with sodium thiosulfate (Na2S2O3) as the sulfur source for the assembly of functionalized (Z)-1,2-bis(arylthio)alkene derivatives is described. Using 0.5 mol% IPr–Pd–Im–Cl2 as the catalyst, a wide range of terminal alkynes and arylhydrazines are well tolerated, thus producing the desired products in good yields with good functional group tolerance and excellent regioselectivity. Moreover, this protocol could be readily scaled up, showing potential applications in organic synthesis and material science. An efficient palladium-catalyzed bisthiolation of terminal alkynes and arylhydrazines with Na2S2O3 as the sulfur source for the assembly of (Z)-1,2-bis(arylthio)alkene derivatives is described.![]()
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Affiliation(s)
- Yin-Long Lai
- College of Chemistry and Civil Engineering, Shaoguan University Shaoguan 512005 P. R. China
| | - Shaoxi Yan
- College of Chemistry and Civil Engineering, Shaoguan University Shaoguan 512005 P. R. China
| | - Dan He
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology Guangzhou 510640 P. R. China
| | - Li-Zhen Zhou
- College of Chemistry and Civil Engineering, Shaoguan University Shaoguan 512005 P. R. China
| | - Zi-Shen Chen
- College of Chemistry and Civil Engineering, Shaoguan University Shaoguan 512005 P. R. China
| | - Yu-Long Du
- College of Chemistry and Civil Engineering, Shaoguan University Shaoguan 512005 P. R. China
| | - Jianxiao Li
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology Guangzhou 510640 P. R. China .,Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology Guangzhou 510640 China
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21
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Hobson K, Carmalt CJ, Bakewell C. Aluminum Amidinates: Insights into Alkyne Hydroboration. Inorg Chem 2021; 60:10958-10969. [PMID: 34270214 PMCID: PMC8388121 DOI: 10.1021/acs.inorgchem.1c00619] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Indexed: 11/30/2022]
Abstract
The mechanism of the aluminum-mediated hydroboration of terminal alkynes was investigated using a series of novel aluminum amidinate hydride and alkyl complexes bearing symmetric and asymmetric ligands. The new aluminum complexes were fully characterized and found to facilitate the formation of the (E)-vinylboronate hydroboration product, with rates and orders of reaction linked to complex size and stability. Kinetic analysis and stoichiometric reactions were used to elucidate the mechanism, which we propose to proceed via the initial formation of an Al-borane adduct. Additionally, the most unstable complex was found to promote decomposition of the pinacolborane substrate to borane (BH3), which can then proceed to catalyze the reaction. This mechanism is in contrast to previously reported aluminum hydride-catalyzed hydroboration reactions, which are proposed to proceed via the initial formation of an aluminum acetylide, or by hydroalumination to form a vinylboronate ester as the first step in the catalytic cycle.
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Affiliation(s)
- Katie Hobson
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - Claire J. Carmalt
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - Clare Bakewell
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
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22
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Dehmel M, Köhler A, Görls H, Kretschmer R. Synthesis, characterization, and reactivity of group 13 hydride complexes based on amido-amine ligands. Dalton Trans 2021; 50:8434-8445. [PMID: 34037004 DOI: 10.1039/d1dt01454d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The preparation of group 13 hydride complexes supported by N,N',N'-substituted 1,2-ethanediamines is reported. Dihydridoalanes LAlH2, for which the aggregation behaviour in solution and in the solid state is modulated by the steric bulk of the aryl substituent, readily react with elemental sulphur affording dinuclear aluminium sulphide complexes. Chloridohydrido trielanes LEHCl (E = B, Al, Ga) have been synthesized as well starting from the hydrochloride salts of the protio-ligands and the chlorido substituent within LAlHCl is readily replaced using Li[N(SiMe3)2]. Depending on the steric bulk of the ligand, the chloridohydrido gallane gives rise to a dinuclear gallium(ii) complex upon heating. All twelve complexes reported in here have been fully characterized and the solid-state structure of eleven complexes has been examined by means of single-crystal X-ray diffraction analysis.
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Affiliation(s)
- Maximilian Dehmel
- Institute of Inorganic and Analytical Chemistry (IAAC), Friedrich Schiller University Jena, Humboldtstraße 8, 07743 Jena, Germany
| | - Angelina Köhler
- Institute of Inorganic and Analytical Chemistry (IAAC), Friedrich Schiller University Jena, Humboldtstraße 8, 07743 Jena, Germany
| | - Helmar Görls
- Institute of Inorganic and Analytical Chemistry (IAAC), Friedrich Schiller University Jena, Humboldtstraße 8, 07743 Jena, Germany
| | - Robert Kretschmer
- Institute of Inorganic and Analytical Chemistry (IAAC), Friedrich Schiller University Jena, Humboldtstraße 8, 07743 Jena, Germany and Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena Philosophenweg 7, 07743 Jena, Germany.
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23
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Li Y, Zhou M, Park S, Dang L. Comparative DFT Study on Dehydrogenative C(sp)-H Elementation (E = Si, Ge, and Sn) of Terminal Alkynes Catalyzed by a Cationic Ruthenium(II) Thiolate Complex. Inorg Chem 2021; 60:6228-6238. [PMID: 33852282 DOI: 10.1021/acs.inorgchem.0c03695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Described herein is a comparative theoretical study of dehydrogenative C(sp)-H functionalizations of a terminal alkyne with group-14-based hydrides (HEEt3; E = Si, Ge, Sn) catalyzed by an Ohki-Tatsumi complex-a cationic Ru(II) complex with a tethered thiolate ligand ([Ru-S] = [(DmpS)Ru(PiPr3)][BAr4F]; Dmp = 2,6-(dimesityl)2C6H3; ArF = 3,5-(CF3)2C6H3). The calculations indicate that the energy barriers for heterolytic cleavage of the H-EEt3 bonds at the Ru-S sites of the Ohki-Tatsumi complex highly vary depending on the group 14 elements from 3.8 kcal/mol (E = Sn) to 10.5 kcal/mol (E = Ge) and 18.5 kcal/mol (E = Si), where Ru and S elements cooperatively serve as the Lewis acid and base, respectively. Likewise, the transfer of the group 14 cation (Et3E+) to the C-C triple bond to generate the β-element-stabilized vinyl cations-the rate-determining step (RDS) of the overall reaction-is predicted to be susceptible to the element's identity [Ea = 36.8 for Sn < 42.9 and Ge < 50.7 for Si (kcal/mol)]. The key transition states involved in the RDS are compared in terms of energy and structure within each system of the group 14 hydrides. The distortion/interaction-activation strain (DIAS) model analysis of the transition states responsible for dehydrogenative stannylation and hydrostannation of a terminal alkyne sheds light on the origin of the experimentally observed kinetic preference toward dehydrogenative C-H stannylation over hydrostannation.
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Affiliation(s)
- Yahui Li
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou, Guangdong 515063, P. R. China
| | - Miaomiao Zhou
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou, Guangdong 515063, P. R. China
| | - Sehoon Park
- Department of Chemistry, Guangdong Technion Israel Institute of Technology, Shantou, Guangdong 515063, China.,Technion-Israel Institute of Technology, Technion City, 32000 Haifa, Israel
| | - Li Dang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou, Guangdong 515063, P. R. China
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24
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Affiliation(s)
- Ruibin Wang
- Department of Chemistry Guangdong Technion Israel Institute of Technology Guangdong 515063 P. R. China
| | - Sehoon Park
- Department of Chemistry Guangdong Technion Israel Institute of Technology Guangdong 515063 P. R. China
- Technion-Israel Institute of Technology Technion City 32000 Haifa Israel
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25
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Pandey VK, Tiwari CS, Rit A. Silver-Catalyzed Hydroboration of C–X (X = C, O, N) Multiple Bonds. Org Lett 2021; 23:1681-1686. [DOI: 10.1021/acs.orglett.1c00106] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Vipin K. Pandey
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| | | | - Arnab Rit
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
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26
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Groutchik K, Jaiswal K, Dobrovetsky R. An air-stable, Zn 2+-based catalyst for hydrosilylation of alkenes and alkynes. Org Biomol Chem 2021; 19:5544-5550. [PMID: 34060566 DOI: 10.1039/d1ob00782c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydrosilylation of C[double bond, length as m-dash]C double and C[triple bond, length as m-dash]C triple bonds is one of the most widely used processes in organosilicon chemistry, mostly catalyzed by Pt-based complexes. We report here the synthesis of an air-stable dicationic Zn2+-based complex in a hemilabile tris(2-methyl-6-pyridylmethyl) phosphine (TmPPh) ligand, 12+[B(C6F5)4]2. When heated, 12+[B(C6F5)4]2 activates Si-H bonds reversibly via ligand/metal cooperation between Lewis acidic Zn2+ and Lewis basic N centers in a frustrated Lewis pair (FLP) type fashion. Consequently, 12+[B(C6F5)4]2 was found to be an effective catalyst for hydrosilylation reactions of C[double bond, length as m-dash]C double and C[triple bond, length as m-dash]C triple bonds. Remarkably, these hydrosilylation reactions can be loaded under aerobic conditions, as well as, in some cases, work under neat conditions. The mechanism of the activation of the Si-H bond and the hydrosilylation reaction is proposed based on experiments and density functional theory (DFT) calculations.
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Affiliation(s)
| | - Kuldeep Jaiswal
- School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel.
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