1
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Mao X, Qiu S, Guo R, Dai Y, Zhang J, Kong L, Xie Z. Cyclic (Alkyl)(Amino)Carbene-Iminoboryl Compounds with Three Formal Oxidation States. J Am Chem Soc 2024; 146:10917-10924. [PMID: 38587904 DOI: 10.1021/jacs.4c01934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
BN/CC isosterism is an effective strategy to build hybrid functional molecules with unique properties. In contrast to the alkynyl iminium salts derived from cyclic (alkyl)(amino)carbenes (CAACs) that feature only one reversible reduction wave, the isoelectronic cationic CAAC-iminoboryl adducts could be singly and doubly reduced smoothly. Both the resultant neutral radical and anionic azaborataallenes bear NBC-mixed allenic structures. The former radical has a high spin-density of 0.55e at CCAAC carbon, yet exhibits formal boron-centered radical reactivity. The latter azaborataallenes feature the nucleophilic CCAAC center and polar N(δ-)═B(δ+)═C(δ-) unit, and readily undergo nucleophilic substitution, isocyanide insertion, dipolar addition and cycloaddition reactions etc. The N-substituents have been shown to have a significant influence on the solid-state structure, thermal stability, and reactivity of azaborataallenes. This work showcases the allenic BN-unsaturated species as versatile building blocks in organic synthesis.
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Affiliation(s)
- Xiaofeng Mao
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong 999077, China
| | - Shuang Qiu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Rui Guo
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Yuyang Dai
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Jie Zhang
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong 999077, China
| | - Lingbing Kong
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Zuowei Xie
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong 999077, China
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
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2
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Han J, Hu C, Li Q, Liu LL, Tung CH, Cui P, Kong L. Derivatization of an Alkylideneborane with B═C Bond Cleavage. Inorg Chem 2023; 62:18820-18824. [PMID: 37935044 DOI: 10.1021/acs.inorgchem.3c03232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
We present the synthesis, structural characterization, and reactivity of alkylideneborane 2, supported by π-donating N-heterocyclic imino and σ-donating N-heterocyclic carbene (NHC) ligands. The incorporation of these ligands effectively weakens the B═C bond strength, leading to enhanced reactivity. Consequently, selective cleavage of the B═C bond can be achieved using pyridine-N-oxide, sulfur, and selenium, resulting in the formation of 1,3-dioxa-2,4-diboretane 3, thioxoborane 4, and selenoborane 5, respectively. Furthermore, intriguing B═C bond insertions with CO2 and CS2 are observed, affording zwitterionic borenium/fluorenide 6 and dithiaboretane 7. The former species 6 is readily converted to transient oxoborane and imidazolium enolate, showcasing the bora-Wittig reaction of alkylideneborane. This investigation highlights the potential of alkylideneborane as a versatile building block for synthesizing novel organoboron compounds through unconventional transformations.
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Affiliation(s)
- Jixing Han
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Chaopeng Hu
- Department of Chemistry and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Qianli Li
- School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China
| | - Liu Leo Liu
- Department of Chemistry and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chen-Ho Tung
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Ping Cui
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Lingbing Kong
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
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3
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Akram MO, Tidwell JR, Dutton JL, Martin CD. Bis(1-Methyl-ortho-Carboranyl)Borane. Angew Chem Int Ed Engl 2023; 62:e202307040. [PMID: 37338991 DOI: 10.1002/anie.202307040] [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: 05/18/2023] [Revised: 06/19/2023] [Accepted: 06/20/2023] [Indexed: 06/22/2023]
Abstract
The Lewis superacid, bis(1-methyl-ortho-carboranyl)borane, is rapidly accessed in two steps. It is a very effective hydroboration reagent capable of B-H addition to alkenes, alkynes, and cyclopropanes. To date, this is the first identified Lewis superacidic secondary borane and most reactive neutral hydroboration reagent.
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Affiliation(s)
- Manjur O Akram
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX, 76798, USA
| | - John R Tidwell
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX, 76798, USA
| | - Jason L Dutton
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Caleb D Martin
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX, 76798, USA
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4
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Tortajada A, Bole LJ, Mu M, Stanford M, Peñas-Defrutos MN, García-Melchor M, Hevia E. Sodium mediated deprotonative borylation of arenes using sterically demanding B(CH 2SiMe 3) 3: unlocking polybasic behaviour and competing lateral borane sodiation. Chem Sci 2023; 14:6538-6545. [PMID: 37350840 PMCID: PMC10283504 DOI: 10.1039/d3sc01705b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/04/2023] [Indexed: 06/24/2023] Open
Abstract
The deprotonative metalation of organic molecules has become a convenient route to prepare functionalised aromatic substrates. Amongst the different metallating reagents available, sodium bases have recently emerged as a more sustainable and powerful alternative to their lithium analogues. Here we report the study of the sterically demanding electrophilic trap B(CH2SiMe3)3 for the deprotonative borylation of arenes using NaTMP (TMP = 2,2,6,6-tetramethylpiperidide) in combination with tridentate Lewis donor PMDETA (PMDETA = N,N,N',N'',N''-pentamethyldiethylenetriamine). Using anisole and benzene as model substrates, unexpected polybasic behaviour has been uncovered, which enables the formal borylation of two equivalents of the relevant arene. The combination of X-ray crystallographic and NMR monitoring studies with DFT calculations has revealed that while the first B-C bond forming process takes place via a sodiation/borylation sequence to furnish [(PMDETA)NaB(Ar)(CH2SiMe3)3] species, the second borylation step is facilitated by the formation of a borata-alkene intermediate, without the need of an external base. For non-activated benzene, it has also been found that under stoichimetric conditions the lateral sodiation of B(CH2SiMe3)3 becomes a competitive reaction pathway furnishing a novel borata-alkene complex. Showing a clear alkali-metal effect, the use of the sodium base is key to access this reactivity, while the metalation/borylation of the amine donor PMDETA is observed instead when LiTMP is used.
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Affiliation(s)
- Andreu Tortajada
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Leonie J Bole
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Manting Mu
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
| | - Martin Stanford
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Marconi N Peñas-Defrutos
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
- IU CINQUIMA/Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid 47071-Valladolid Spain
| | - Max García-Melchor
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
| | - Eva Hevia
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
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5
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Škoch K, Chen C, Daniliuc CG, Kehr G, Erker G. A deprotonation pathway to reactive [B]CH 2 boraalkenes. Dalton Trans 2022; 51:7695-7704. [PMID: 35521694 DOI: 10.1039/d2dt01193j] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The BH compounds IMes(ArF)BH(NTf2) (ArF: C6F5 or FpXyl) were converted to the IMes(ArF)BCH2 boraalkenes in a three step reaction sequence of B-methylation with methyllithium, hydride abstraction and deprotonation. The BCH2 boraalkenes reacted with elemental sulfur to give a thiaborirane product. They underwent [2+2] cycloaddition reactions with carbon dioxide or sulfur dioxide to give four-membered boron containing heterocycles. The boraalkenes added strongly Lewis acidic boranes at their CH2 carbon atoms. The corresponding HB(C6F5)2/boraalkene adduct reduced carbon monoxide to a -OCH(C6F5)- moiety inside a five-membered heterocycle at the B-CH2-B template. The boraalkenes reacted with the [(Me2S)AuCl] reagent to form the corresponding (boraalkene)AuCl complexes.
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Affiliation(s)
- Karel Škoch
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149 Münster, Germany.
| | - Chaohuang Chen
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149 Münster, Germany.
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149 Münster, Germany.
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149 Münster, Germany.
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149 Münster, Germany.
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6
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Erker G, Li J, Daniliuc CG, Kehr G. An Olefin-based Multi-component Reaction to 1,2-Azaborolidine Derivatives. Dalton Trans 2022; 51:1775-1778. [DOI: 10.1039/d1dt04337d] [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
Reaction of the borane FmesBH2·SMe2 [Fmes: 2,4,6-tris(trifluoro-methyl)phenyl] with two molar equivs of a small series of 1-alkenes followed by treatment with two molar equivalents of the bulky isonitrile CN-Xyl (Xyl:...
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7
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Chen C, Daniliuc CG, Kehr G, Erker G. N-Heterocyclic Carbene Stabilized 1-Bora-1,3-butadienes. J Am Chem Soc 2021; 143:21312-21320. [PMID: 34894685 DOI: 10.1021/jacs.1c09774] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Deprotonation of [(NHC)(Fmes)B-allyl]+ borenium cations (NHC, IMes (a) or IMe2 (b); Fmes, 2,4,6-(CF3)3C6H2) provides an easy entry to the NHC-stabilized 1-bora-1,3-butadienes. They feature a planar s-trans-conformation just like 1,3-butadiene. The 1-borabutadiene 7a undergoes hydroboration reactions; the HB(C6F5)2 hydroboration product is trapped with CO or an isonitrile to give the respective cyclic zwitterionic borenium-borate enolate or enamide products. 1-Borabutadiene 7b undergoes 1,4-chalcogenation with elemental sulfur or selenium, and it gives the six-membered heterocyclic 1,4-addition product with the S═O bond of sulfur dioxide. Compound 7b served as a precursor for the formation of a borylated η3-allyl ligand at Ru. 7b formed a Rh complex by reaction with [Rh(ethylene)2Cl]2. It subsequently underwent an intramolecular C-H activation reaction to a mixture of η3-methyl-boraallyl Rh complex isomers.
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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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8
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Li J, Daniliuc CG, Kehr G, Erker G. Three‐Component Reaction to 1,4,2‐Diazaborole‐Type Heteroarene Systems. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jun Li
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
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9
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Li J, Daniliuc CG, Kehr G, Erker G. Three-Component Reaction to 1,4,2-Diazaborole-Type Heteroarene Systems. Angew Chem Int Ed Engl 2021; 60:27053-27061. [PMID: 34597449 DOI: 10.1002/anie.202111946] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Indexed: 12/14/2022]
Abstract
The borane FmesBH2 reacts in a three-component reaction with an isonitrile and a small series of organonitriles to give rare examples of the class of dihydro-1,4,2-diazaborole derivatives. In a related way, annulated BN-indolizine derivatives became conveniently available, as were dihydro-1,4,2-oxaza- or thiazaborole derivatives. The nucleophilic framework of a dihydro-1,4,2-diazaborole example allowed for an uncatalyzed acylation reaction. It also served as a 1,3-dipolar reagent and underwent a [3+2] cycloaddition/[4+2] cycloreversion sequence when treated with methyl propiolate to give the respective pyrrole product. The [3+2] cycloaddition product of a dihydro-1,4,2-diazaborole derivative with N-phenylmaleimide was isolated and its heterobicyclo[2.2.1]heptane derived structure characterized by X-ray diffraction.
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Affiliation(s)
- Jun Li
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
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10
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Abstract
We report the phospha-bora-Wittig reaction for the direct preparation of phosphaalkenes from aldehydes, ketones, esters, or amides. The transient phosphaborene Mes*P═B-NR2 reacts with carbonyl compounds to form 1,2,3-phosphaboraoxetanes, analogues of oxaphosphetane intermediates in the classical Wittig reaction. 1,2,3-Phosphaboraoxetanes undergo thermal or Lewis acid-promoted cycloreversion, yielding phosphaalkenes. Experimental and density functional theory studies reveal far-reaching similarities between classical and phospha-bora-Wittig reactions.
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Affiliation(s)
- Andryj M Borys
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom
| | - Ella F Rice
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom
| | - Gary S Nichol
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom
| | - Michael J Cowley
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom
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11
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Abstract
Structurally authenticated free B-alkyl boroles are presented and electronic implications of alkyl substitution were assessed. Deprotonation of a boron-bound exocyclic methyl group in a B-methyl borole yields the first 5-boratafulvene anion-an isomer to boratabenzene. Boratafulvene was structurally characterized and its electronic structure probed by DFT calculations. The pKa value of the exocyclic B-CH3 in a set of boroles was computationally approximated and confirmed a pronounced acidic character caused by the boron atom embedded in an anti-aromatic moiety. The non-aromatic boratafulvene reacts as a C-centered nucleophile with the mild electrophile Me3 SnCl to give a stannylmethyl borole, regenerating the anti-aromaticity. As nucleophilic synthons for boroles, boratafulvenes thus open an entirely new avenue for synthetic strategies toward this highly reactive class of heterocycles. Boratafulvene reacts as a methylene transfer reagent in a bora-Wittig-type reaction generating a borole oxide.
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Affiliation(s)
- Tobias Heitkemper
- Institut für Anorganische ChemieGeorg-August-Universität GöttingenTammannstrasse 437077GöttingenGermany
| | - Leonard Naß
- Institut für Anorganische ChemieGeorg-August-Universität GöttingenTammannstrasse 437077GöttingenGermany
| | - Christian P. Sindlinger
- Institut für Anorganische ChemieGeorg-August-Universität GöttingenTammannstrasse 437077GöttingenGermany
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12
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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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13
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Heitkemper T, Naß L, Sindlinger CP. Ein Boratafulven. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107968] [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)
- Tobias Heitkemper
- Institut für Anorganische Chemie Georg-August-Universität Göttingen Tammannstraße 4 37077 Göttingen Deutschland
| | - Leonard Naß
- Institut für Anorganische Chemie Georg-August-Universität Göttingen Tammannstraße 4 37077 Göttingen Deutschland
| | - Christian P. Sindlinger
- Institut für Anorganische Chemie Georg-August-Universität Göttingen Tammannstraße 4 37077 Göttingen Deutschland
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14
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Li J, Daniliuc CG, Matern J, Fernández G, Kehr G, Erker G. Multi-component synthesis of dihydro-1,3-azaborinine derived oxindole isosteres. Chem Commun (Camb) 2021; 57:7689-7692. [PMID: 34259251 DOI: 10.1039/d1cc02557k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report on the synthesis of the first examples of 1,3-azaborinine derived oxindole systems, the BN-isosteres of the important compound class of the oxindoles. Hydroboration of terminal aryl acetylenes with FmesBH2, followed by treatment with 2 equiv. of a glycine ester derived isonitrile gave a small series of 1,3-azaborinine derived oxindoles. The new BN-oxindoles show interesting photophysical behavior.
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Affiliation(s)
- Jun Li
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany.
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany.
| | - Jonas Matern
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany.
| | - Gustavo Fernández
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany.
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany.
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany.
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15
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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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16
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Bartholome TA, Martinez JJ, Kaur A, Wilson DJD, Dutton JL, Martin CD. Borataalkene Hydrofunctionalization Reactions. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00261] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tyler A. Bartholome
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Jesse J. Martinez
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Aishvaryadeep Kaur
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - David J. D. Wilson
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Jason L. Dutton
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Caleb D. Martin
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
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17
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18
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Abstract
Boron-Wittig reaction as the condensation of lithium α-bis(boryl)carbanions with carbonyl derivatives on route to substituted borylalkenes.
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Affiliation(s)
- Ana B. Cuenca
- Dept. Organic and Pharmaceutic Chemistry
- Institut Químic de Sarrià
- Universitat Ramon Llull
- Barcelona
- Spain
| | - Elena Fernández
- Dept. Química Física e Inorgánica
- University Rovira i Virgili
- Tarragona
- Spain
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19
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Dilchert K, Scherpf T, Gessner VH. Carbenoid‐Mediated Formation and Activation of Element‐Element and Element–Hydrogen Bonds. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Katharina Dilchert
- Chair of Inorganic Chemistry II Faculty of Chemistry and Biochemistry Ruhr‐University Bochum Universitätsstraße 150 44801 Bochum Germany
| | - Thorsten Scherpf
- Chair of Inorganic Chemistry II Faculty of Chemistry and Biochemistry Ruhr‐University Bochum Universitätsstraße 150 44801 Bochum Germany
| | - Viktoria H. Gessner
- Chair of Inorganic Chemistry II Faculty of Chemistry and Biochemistry Ruhr‐University Bochum Universitätsstraße 150 44801 Bochum Germany
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20
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Watanabe K, Ueno A, Tao X, Škoch K, Jie X, Vagin S, Rieger B, Daniliuc CG, Letzel MC, Kehr G, Erker G. Reactions of an anionic chelate phosphane/borata-alkene ligand with [Rh(nbd)Cl] 2, [Rh(CO) 2Cl] 2 and [Ir(cod)Cl] 2. Chem Sci 2020; 11:7349-7355. [PMID: 33209245 PMCID: PMC7654189 DOI: 10.1039/d0sc02223c] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 06/18/2020] [Indexed: 11/21/2022] Open
Abstract
Borata-alkenes can serve as anionic olefin equivalent ligands in transition metal chemistry. A chelate ligand of this type is described and used for metal coordination. Deprotonation of the Mes2P(CH2)2B(C6F5)2 frustrated Lewis pair in the α-CH[B] position gave the methylene-bridged phosphane/borata-alkene anion. It reacted with the [Rh(nbd)Cl] or [Rh(CO)2Cl] dimers to give the respective neutral chelate [P/C[double bond, length as m-dash]B][Rh] complexes. The reaction of the [P/C[double bond, length as m-dash]B]- anion with [Ir(cod)Cl]2 proceeded similarly, only that the complex underwent a subsequent oxidative addition reaction at the mesityl substituent. Both the resulting Ir(iii)hydride complex 15 and the P/borata-alkene Rh system 12 were used as hydrogenation catalysts. The [P/C[double bond, length as m-dash]B(C6F5)2]Rh(nbd) complex 12 served as a catalyst for arylacetylene polymerization.
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Affiliation(s)
- Kohei Watanabe
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany .
| | - Atsushi Ueno
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany .
| | - Xin Tao
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany .
| | - Karel Škoch
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany .
| | - Xiaoming Jie
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany .
| | - Sergei Vagin
- Wacker-Lehrstuhl für Makromolekulare Chemie , Fakultät für Chemie , Technische Universität München , Lichtenbergstraße 4, 85747 Garching bei München , Germany
| | - Bernhard Rieger
- Wacker-Lehrstuhl für Makromolekulare Chemie , Fakultät für Chemie , Technische Universität München , Lichtenbergstraße 4, 85747 Garching bei München , Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany .
| | - Matthias C Letzel
- 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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21
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Kobayashi A, Suzuki K, Kitamura R, Yamashita M. Formation of BCBH/BCBCl Four-Membered Rings by Complexation of Boron- and Nitrogen-Substituted Acetylene with Hydro-/Chloroboranes. Organometallics 2020. [DOI: 10.1021/acs.organomet.9b00876] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Akemi Kobayashi
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Katsunori Suzuki
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Ryo Kitamura
- Department of Applied Chemistry, Graduate School of Science and Engineering, Chuo University, Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Makoto Yamashita
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
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22
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Li J, Daniliuc CG, Mück-Lichtenfeld C, Kehr G, Erker G. Multi-Component Synthesis of Rare 1,3-Dihydro-1,3-azaborinine Derivatives: Application of a Bora-Nazarov Type Reaction. Angew Chem Int Ed Engl 2019; 58:15377-15380. [PMID: 31418990 DOI: 10.1002/anie.201909530] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Indexed: 11/09/2022]
Abstract
The twofold hydroboration products of (Fmes)BH2 ⋅SMe2 with a series of alkynes (2-butyne, arylethynes) react with two molar equiv of 2,6-dimethylphenyl isocyanide (CN-Xyl) at 80 °C to give rare examples of 1,3-azaborinine derivatives. A mechanistic study revealed a reaction course involving insertion of one isonitrile followed by a bora-Nazarov type ring-closure reaction and subsequent isonitrile insertion to give the respective 1,3-dihydro-1,3-azaborinines 5.
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Affiliation(s)
- Jun Li
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
| | - Christian Mück-Lichtenfeld
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149, Münster, Germany
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23
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Li J, Daniliuc CG, Mück‐Lichtenfeld C, Kehr G, Erker G. Multi‐Component Synthesis of Rare 1,3‐Dihydro‐1,3‐azaborinine Derivatives: Application of a Bora‐Nazarov Type Reaction. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201909530] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Jun Li
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
| | - Christian Mück‐Lichtenfeld
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraβe 40 48149 Münster Germany
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24
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Kovalenko M, Yarmoliuk DV, Serhiichuk D, Chernenko D, Smyrnov V, Breslavskyi A, Hryshchuk OV, Kleban I, Rassukana Y, Tymtsunik AV, Tolmachev AA, Kuchkovska YO, Grygorenko OO. The Boron-Wittig Olefination of Aldehydes and Ketones with Bis[(pinacolato)boryl]methane: an Extended Reaction Scope. European J Org Chem 2019. [DOI: 10.1002/ejoc.201900648] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Maksym Kovalenko
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
| | - Dmytro V. Yarmoliuk
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- Taras Shevchenko National University of Kyiv; Volodymyrska Street 60 01601 Kyiv Ukraine
| | - Dmytro Serhiichuk
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
| | - Daria Chernenko
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”; Prospect Peremogy 37 03056 Kyiv Ukraine
| | - Vladyslav Smyrnov
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- Taras Shevchenko National University of Kyiv; Volodymyrska Street 60 01601 Kyiv Ukraine
| | - Artur Breslavskyi
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
| | - Oleksandr V. Hryshchuk
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- Taras Shevchenko National University of Kyiv; Volodymyrska Street 60 01601 Kyiv Ukraine
| | - Ihor Kleban
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- Institute of Organic Chemistry; National Academy of Sciences of Ukraine; Murmanska Street 5 02660 Kyiv Ukraine
| | - Yuliya Rassukana
- Institute of Organic Chemistry; National Academy of Sciences of Ukraine; Murmanska Street 5 02660 Kyiv Ukraine
- National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”; Prospect Peremogy 37 03056 Kyiv Ukraine
| | - Andriy V. Tymtsunik
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”; Prospect Peremogy 37 03056 Kyiv Ukraine
| | - Andrey A. Tolmachev
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- Taras Shevchenko National University of Kyiv; Volodymyrska Street 60 01601 Kyiv Ukraine
| | - Yuliya O. Kuchkovska
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- Taras Shevchenko National University of Kyiv; Volodymyrska Street 60 01601 Kyiv Ukraine
| | - Oleksandr O. Grygorenko
- Enamine Ltd. (www.enamine.net); Chervonotkatska Street 78 02094 Kyiv Ukraine
- Taras Shevchenko National University of Kyiv; Volodymyrska Street 60 01601 Kyiv Ukraine
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25
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Liu S, Légaré MA, Hofmann A, Rempel A, Hagspiel S, Braunschweig H. Synthesis of unsymmetrical B 2E 2 and B 2E 3 heterocycles by borylene insertion into boradichalcogeniranes. Chem Sci 2019; 10:4662-4666. [PMID: 31123576 PMCID: PMC6495701 DOI: 10.1039/c9sc00657e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 03/18/2019] [Indexed: 12/05/2022] Open
Abstract
We report the selective insertion of a range of borylene fragments into the E-E bonds (E = S, Se, Te) of cyclic boron dichalcogenides. This method provides facile synthetic access to a variety of symmetrical and unsymmetrical four- and five-membered rings.
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Affiliation(s)
- Siyuan Liu
- Institut für Anorganische Chemie , 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
| | - Marc-André Légaré
- Institut für Anorganische Chemie , 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
| | - Alexander Hofmann
- Institut für Anorganische Chemie , 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
| | - Anna Rempel
- Institut für Anorganische Chemie , 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
| | - Stephan Hagspiel
- Institut für Anorganische Chemie , 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
- Institut für Anorganische Chemie , 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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26
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Wang L, Li J, Deng D, Daniliuc CG, Mück-Lichtenfeld C, Kehr G, Erker G. Carbon–carbon bond forming reactions of acetylenic esters and ketones within frustrated phosphane/borane Lewis pair frameworks. Dalton Trans 2019; 48:11921-11926. [DOI: 10.1039/c9dt02624j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The three-component reactions of bulky diarylbutenylphosphanes with dimethyl acetylenedicarboxylate and the strong boron Lewis acid B(C6F5)3 give the ylide-substituted cyclopropane derivatives.
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Affiliation(s)
- Long Wang
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Jun Li
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Dongsheng Deng
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | | | - Gerald Kehr
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
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27
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Ueno A, Tao X, Daniliuc CG, Kehr G, Erker G. Unusual 1,1-Hydroboration Route to a Reactive Unsaturated Vicinal Frustrated Phosphane/Borane Lewis Pair. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00481] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Atsushi Ueno
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Xin Tao
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149 Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, 48149 Münster, Germany
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28
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Wang T, Daniliuc CG, Mück-Lichtenfeld C, Kehr G, Erker G. Formation of Reactive π-Conjugated Frustrated N/B Pairs by Borane-Induced Propargyl Amine Rearrangement. J Am Chem Soc 2018; 140:3635-3643. [PMID: 29444567 DOI: 10.1021/jacs.7b11958] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
N-Propargyltetramethylpiperidine reacts with a series of trans-alkenyl-B(C6F5)2 compounds to give the substituted alkenyl-bridged frustrated N/B Lewis pairs 5. Their structures and spectroscopic features indicate a pronounced participation of the mesomeric s-trans-iminium/borata-alkene resonance form. The compounds are thought to be formed in a stepwise addition/rearrangement process which is initiated by a trans-1,2-amine/borane FLP addition to the carbon-carbon triple bond to generate a reactive zwitterionic aziridinium/alkenylborate intermediate. Subsequent alkenylborate attack leads to opening of the activated three-membered heterocycle with clean formation of the products 5a-c. Treatment of the propargyl-TMP substrate with B(C6F5)3 gave a stable example of such an aziridinium/borate betaine, which was isolated and amply characterized. The products 5a-c are active N/B FLPs. They split dihydrogen heterolytically under mild conditions to give the respective NH+/BH- products 9a-c. These contain Z-configurated core C═C double bonds, which indicates rotational equilibration around the central C-C bond of 5a-c during this reaction. Structural and chemical features of the 5c system were analyzed by DFT calculations.
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Affiliation(s)
- Tongdao Wang
- 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
| | - Christian Mück-Lichtenfeld
- 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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29
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Wang L, Jian Z, Daniliuc CG, Kehr G, Erker G. Formation of borata-alkene/iminium zwitterions by ynamine hydroboration. Dalton Trans 2018; 47:10853-10856. [DOI: 10.1039/c8dt02435a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ynamine TMP–CC–CH3 adds HB(C6F5)2 to give the unsaturated C2-bridged N/B FLP, which shows a marked participation of the mesomeric zwitterionic borata-alkene/iminium form.
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Affiliation(s)
- Long Wang
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Zhongbao Jian
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
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