1
|
Scholz AS, Bolte M, Virovets A, Peresypkina E, Lerner HW, Anstöter CS, Wagner M. Tetramerization of BEB-Doped Phenalenyls to Obtain (BE) 8-[16]Annulenes (E = N, O). J Am Chem Soc 2024; 146:12100-12112. [PMID: 38635878 DOI: 10.1021/jacs.4c02163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
Two (BE)8-[16]annulenes were prepared and fully characterized by experimental and quantum-chemical means (1, E = N; 2, E = O). The 1,8-naphthalenediyl-bridged diborane(6) 3 served as their common starting material, which was treated with [Al(NH3)6]Cl3 to form 1 (91% yield) or with 1,8-naphthalenediboronic acid anhydride to form 2 (93% yield). As a result, the heteroannulenes 1 and 2 are supported by four aromatic "clamps" and may also be viewed as NH- or O-bridged cyclic tetramers of BNB- or BOB-doped phenalenyls. X-ray crystallography on mono-, di-, and tetraadducts 2·thf, 2·py2, and 2·py4 showed that 2 is an oligotopic Lewis acid (thf/py: tetrahydrofuran/pyridine donor). The applicability of 2 also as a Lewis basic ligand in coordination chemistry was demonstrated by the synthesis of the mononuclear Ag+ complex [Ag(py)2(2·py4)]+ and the dinuclear Pb2+ complex 6. During the assembly of 6, the rearrangement of 2 led to the formation of two (BO)9-macrocycles linked by two BOB-phenalenyls to form a nanometer-sized cage with four negatively charged, tetracoordinated B atoms. Both 1 and 2 show several redox waves in the cathodic regions of the cyclic voltammograms. An in-depth assessment of the consequences of electron injection on the aromaticity of 1 and 2 was achieved by electronic structure calculations. 1 and 2 are proposed to exhibit aromatic switching capabilities in the [16]annulene motif.
Collapse
Affiliation(s)
- Alexander S Scholz
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Michael Bolte
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Alexander Virovets
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Eugenia Peresypkina
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Hans-Wolfram Lerner
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Cate S Anstöter
- EaStCHEM School of Chemistry, University of Edinburgh, EH8 9YLEdinburgh,U.K
| | - Matthias Wagner
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| |
Collapse
|
2
|
Gupta D, Einholz R, Bettinger HF. Strain induced reactivity of cyclic iminoboranes: the (2 + 2) cycloaddition of a 1 H-1,3,2-diazaborepine with ethene. Chem Sci 2024; 15:666-674. [PMID: 38179531 PMCID: PMC10763563 DOI: 10.1039/d3sc04901a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Accepted: 11/19/2023] [Indexed: 01/06/2024] Open
Abstract
Iminoboranes have gathered immense attention due to their reactivity and potential applications as isoelectronic and isosteric alkynes. While cyclic alkynes are well investigated and useful reagents, cyclic iminoboranes are underexplored and their existence was inferred only via trapping experiments. We report the first direct spectroscopic evidence of a cyclic seven-membered iminoborane, 1-(tert-butyldimethylsilyl)-1H-1,3,2-diazaborepine 2, under cryogenic matrix isolation conditions. The amino-iminoborane 2 was photochemically generated in solid argon at 4 K from 2-azido-1-(tert-butyldimethylsilyl)-1,2-dihydro-1,2-azaborinine (3) and was characterized using FT-IR, UV-vis spectroscopy, and computational chemistry. The characteristic BN stretching vibration (1751 cm-1) is shifted by about 240 cm-1 compared to linear amino-iminoboranes indicating a significant weakening of the bond. The Lewis acidity value determined computationally (LAB = 9.1 ± 2.6) is similar to that of boron trichloride, and twelve orders of magnitude lower than that of 1,2-azaborinine (BN-aryne, LAB = 21.5 ± 2.6), a six-membered cyclic iminoborane. In contrast to the latter, the reduced ring strain of 2 precludes nitrogen fixation, but it unexpectedly allows facile (2 + 2) cycloaddition reaction with C2H4 under matrix isolation conditions at 30 K.
Collapse
Affiliation(s)
- Divanshu Gupta
- Institut für Organische Chemie, Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Ralf Einholz
- Institut für Organische Chemie, Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Holger F Bettinger
- Institut für Organische Chemie, Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| |
Collapse
|
3
|
Gupta D, Keck C, Tönshoff C, Bhagat V, Strobel R, Eder M, Baylère P, Labat S, Chrostowska A, Bettinger HF. Direct Spectroscopic Identification of BN-Arynes and Subtle Steric Effects on Nitrogen Fixation. Chemistry 2023; 29:e202302444. [PMID: 37932038 DOI: 10.1002/chem.202302444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Indexed: 11/08/2023]
Abstract
1,2-Azaborinines are the BN analogues of arynes through exchange of the formal CC triple bond by an isoelectronic BN bond. The BN-arynes are an underexplored class of reactive intermediates. Dibenzo[c,e][1,2]azaborinine (10,9-BN-phenanthryne) 1 was inferred as reactive intermediate by trapping reactions. Here it is shown that 1 can be generated in the gas phase by thermolysis from the pyridine adduct of 9-azido-9-borafluorene by cleavage of the dative bond with pyridine and dinitrogen extrusion. The ionization potential of 1 is 8.2 eV with ionization resulting from the π HOMO. Under cryogenic matrix isolation conditions, 9-azido-9-borafluorene photolysis results in isomerization to the dinitrogen adduct of 1 without involvement of a triplet borylnitrene intermediate. Photochemical nitrogen extrusion from 1 ⋅ N2 is not possible and nitrogen fixation is irreversible under cryogenic conditions. In contrast, 2,4,7,9-tetra-tert-butyldibenzo[c,e][1,2]azaborinine can be photogenerated from the corresponding azidoborole precursor under cryogenic matrix isolation conditions, and nitrogen fixation is precluded due to steric hindrance. The BN stretching vibration at about 1750 cm-1 is much weaker than in typical linear diaryl iminoboranes.
Collapse
Affiliation(s)
- Divanshu Gupta
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Constanze Keck
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Christina Tönshoff
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Virinder Bhagat
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Raphael Strobel
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Manuel Eder
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Patrick Baylère
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, UMR 5254, 64000, Pau, France
| | - Stéphane Labat
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, UMR 5254, 64000, Pau, France
| | - Anna Chrostowska
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, UMR 5254, 64000, Pau, France
| | - Holger F Bettinger
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| |
Collapse
|
4
|
Krebs J, Häfner A, Fuchs S, Guo X, Rauch F, Eichhorn A, Krummenacher I, Friedrich A, Ji L, Finze M, Lin Z, Braunschweig H, Marder TB. Backbone-controlled LUMO energy induces intramolecular C-H activation in ortho-bis-9-borafluorene-substituted phenyl and o-carboranyl compounds leading to novel 9,10-diboraanthracene derivatives. Chem Sci 2022; 13:14165-14178. [PMID: 36540825 PMCID: PMC9728567 DOI: 10.1039/d2sc06057d] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 11/05/2022] [Indexed: 08/11/2023] Open
Abstract
The choice of backbone linker for two ortho-bis-(9-borafluorene)s has a great influence on the LUMO located at the boron centers and, therefore, the reactivity of the respective compounds. Herein, we report the room temperature rearrangement of 1,2-bis-(9-borafluorenyl)-ortho-carborane, C2B10H10-1,2-[B(C12H8)]2 ([2a]) featuring o-carborane as the inorganic three-dimensional backbone and the synthesis of 1,2-bis-(9-borafluorenyl)benzene, C6H4-1,2-[B(C12H8)]2 (2b), its phenylene analog. DFT calculations on the transition state for the rearrangement support an intramolecular C-H bond activation process via an SEAr-like mechanism in [2a], and predicted that the same rearrangement would take place in 2b, but at elevated temperatures, which indeed proved to be the case. The rearrangement gives access to 3a and 3b as dibora-benzo[a]fluoroanthene isomers, a form of diboron polycyclic aromatic hydrocarbon (PAH) that had yet to be explored. The isolated compounds 2b, 3a, and 3b were fully characterized by NMR, HRMS, cyclic voltammetry (CV), single-crystal X-ray diffraction analysis, and photophysical measurements, supported by DFT and TD-DFT calculations.
Collapse
Affiliation(s)
- Johannes Krebs
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Alena Häfner
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Sonja Fuchs
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Xueying Guo
- Department of Chemistry, The Hong Kong University of Science and Technology Clear Water Bay Hong Kong
| | - Florian Rauch
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Antonius Eichhorn
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Ivo Krummenacher
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Alexandra Friedrich
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Lei Ji
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE), Northwestern Polytechnical University 127 West Youyi Road Xi'an Shaanxi P. R. China
| | - Maik Finze
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Zhenyang Lin
- Department of Chemistry, The Hong Kong University of Science and Technology Clear Water Bay Hong Kong
| | - Holger Braunschweig
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Todd B Marder
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| |
Collapse
|
5
|
Vogler D, Schöner M, Kaifer E, Himmel H. Bistriazoles Connected Through a B−B Bridge, Synthesized by Highly Selective Dipolar Cycloaddition Reactions of a Diazido‐diborane(4). Chemistry 2022; 28:e202201389. [PMID: 35703332 PMCID: PMC9544427 DOI: 10.1002/chem.202201389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Indexed: 11/11/2022]
Abstract
In this work we report the first cycloaddition reactions between a diazido diborane(4) and terminal alkynes, providing unique access to bis‐1,2,3‐triazoles connected by a B−B bridge. The catalyst‐free reactions are highly selective, yielding exclusively the thermodynamically disfavored bis‐1,4‐triazoles. The reactions are enabled by the high thermal stability of the diazido‐diborane [B(hpp)(N3)]2 (hpp=1,3,4,6,7,8‐hexahydro‐2H‐pyrimido[1,2‐α]pyrimidinate). Due to the tetra‐coordinate boron atoms in this reagent, the reactions are tolerant with respect to the introduction of Lewis‐basic groups at the alkyne. The scope and limitations of the new reactions are discussed.
Collapse
Affiliation(s)
- Daniel Vogler
- Anorganisch-Chemisches Institut Ruprecht-Karls Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Maximilian Schöner
- Anorganisch-Chemisches Institut Ruprecht-Karls Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Elisabeth Kaifer
- Anorganisch-Chemisches Institut Ruprecht-Karls Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Hans‐Jörg Himmel
- Anorganisch-Chemisches Institut Ruprecht-Karls Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| |
Collapse
|
6
|
Bischof T, Guo X, Krummenacher I, Beßler L, Lin Z, Finze M, Braunschweig H. Alkene insertion reactivity of a o-carboranyl-substituted 9-borafluorene. Chem Sci 2022; 13:7492-7497. [PMID: 35872816 PMCID: PMC9244080 DOI: 10.1039/d2sc02750j] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 06/01/2022] [Indexed: 11/24/2022] Open
Abstract
The synthesis of 9-borafluorene with an electron-withdrawing o-carboranyl substituent and its reactions with a series of alkenes are described. The o-carboranyl substituent is bonded via one of the cluster carbon atoms to the boron atom of the 9-borafluorene moiety. In all cases, the reactions afford partly saturated analogs of borepins (i.e. 6,7-dihydroborepins) by unprecedented alkene insertion into the endocyclic B–C bond of the borole ring. Comparative studies with 9-bromo-9-borafluorene illustrate the superior insertion reactivity of the carboranyl-substituted derivative. A suite of experimental and computational techniques disclose the unique properties of the 9-borafluorene and provide insight into how the 9-carboranyl substituent affects its chemical reactivity. A 9-carboranyl-substituted 9-borafluorene is reported, which is capable of undergoing efficient ring expansion to 6,7-dihydroborepins by a previously unknown alkene insertion.![]()
Collapse
Affiliation(s)
- Tobias Bischof
- 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
| | - Xueying Guo
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China
| | - Ivo Krummenacher
- 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
| | - Lukas Beßler
- 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
| | - Zhenyang Lin
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China
| | - Maik Finze
- 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
| |
Collapse
|
7
|
Keck C, Hahn J, Gupta D, Bettinger HF. Solution Phase Reactivity of Dibenzo[c,e][1,2]azaborinine: Activation and Insertion into Si-E Single Bonds (E=H, OSi(CH 3 ) 3 , F, Cl) by a BN-Aryne. Chemistry 2021; 28:e202103614. [PMID: 34854508 PMCID: PMC9299606 DOI: 10.1002/chem.202103614] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Indexed: 11/24/2022]
Abstract
The boron‐nitrogen analogue of ortho‐benzyne, 1,2‐azaborinine, is a reactive intermediate that features a formal boron‐nitrogen triple bond. We here show by combining experimental and computational techniques that the Lewis acidity of the boron center of dibenzo[c,e][1,2]azaborinine allows interaction with the silicon containing single bonds Si−E through the silicon bonding partner E (E=F, Cl, OR, H). The binding to boron activates the Si−E bonds for subsequent insertion reaction. This shows that the BN‐aryne is a ferocious species that even can activate and insert into the very strong Si−F bond.
Collapse
Affiliation(s)
- Constanze Keck
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Jennifer Hahn
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Divanshu Gupta
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Holger F Bettinger
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| |
Collapse
|
8
|
Ouadoudi O, Kaehler T, Bolte M, Lerner HW, Wagner M. One tool to bring them all: Au-catalyzed synthesis of B,O- and B,N-doped PAHs from boronic and borinic acids. Chem Sci 2021; 12:5898-5909. [PMID: 34168815 PMCID: PMC8179653 DOI: 10.1039/d1sc00543j] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The isoelectronic replacement of C
Created by potrace 1.16, written by Peter Selinger 2001-2019
]]>
C bonds with −BN+ bonds in polycyclic aromatic hydrocarbons (PAHs) is a widely used tool to prepare novel optoelectronic materials. Far less well explored are corresponding B,O-doped PAHs, although they have a similarly high application potential. We herein report on the modular synthesis of B,N- and B,O-doped PAHs through the [Au(PPh3)NTf2]-catalyzed 6-endo-dig cyclization of BN–H and BO–H bonds across suitably positioned C
Created by potrace 1.16, written by Peter Selinger 2001-2019
]]>
C bonds in the key step. Readily available, easy-to-handle o-alkynylaryl boronic and borinic acids serve as starting materials, which are either cyclized directly or first converted into the corresponding aminoboranes and then cyclized. The reaction even tolerates bulky mesityl substituents on boron, which later kinetically protect the formed B,N/O-PAHs from hydrolysis or oxidation. Our approach is also applicable for the synthesis of rare doubly B,N/O-doped PAHs. Specifically, we prepared 1,2-B,E-naphthalenes and -anthracenes, 1,5-B2-2,6-E2-anthracenes (E = N, O) as well as B,O2-containing and unprecedented B,N,O-containing phenalenyls. Selected examples of these compounds have been structurally characterized by X-ray crystallography; their optoelectronic properties have been studied by cyclic voltammetry, electron spectroscopy, and quantum-chemical calculations. Using a new unsubstituted (B,O)2-perylene as the substrate for late-stage functionalization, we finally show that the introduction of two pinacolatoboryl (Bpin) substituents is possible in high yield and with perfect regioselectivity via an Ir-catalyzed C–H borylation approach. Singly and doubly B,E-doped PAHs were synthesized using a protocol that starts from easy-to-handle boronic and borinic acids and offers the possibility to choose between the preparation of B,O- and B,N-PAHs in the final reaction step.![]()
Collapse
Affiliation(s)
- Omar Ouadoudi
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt Max-von-Laue-Straße 7 D-60438 Frankfurt (Main) Germany
| | - Tanja Kaehler
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt Max-von-Laue-Straße 7 D-60438 Frankfurt (Main) Germany
| | - Michael Bolte
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt Max-von-Laue-Straße 7 D-60438 Frankfurt (Main) Germany
| | - Hans-Wolfram Lerner
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt Max-von-Laue-Straße 7 D-60438 Frankfurt (Main) Germany
| | - Matthias Wagner
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt Max-von-Laue-Straße 7 D-60438 Frankfurt (Main) Germany
| |
Collapse
|
9
|
Su X, Bartholome TA, Tidwell JR, Pujol A, Yruegas S, Martinez JJ, Martin CD. 9-Borafluorenes: Synthesis, Properties, and Reactivity. Chem Rev 2021; 121:4147-4192. [DOI: 10.1021/acs.chemrev.0c01068] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Xiaojun Su
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Tyler A. Bartholome
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - John R. Tidwell
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Alba Pujol
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Sam Yruegas
- 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
| | - Caleb D. Martin
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| |
Collapse
|
10
|
Keck C, Maichle-Mössmer C, Bettinger HF. Photo electron transfer induced desilylation of N,N-bis(trimethylsilyl)aminodibenzoborole to aminodibenzoborole. Chem Commun (Camb) 2019; 55:7470-7473. [DOI: 10.1039/c9cc03415c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photoinduced desilylation proceeds by single electron transfer and yields the first example of an unsubstituted aminoborole derivative.
Collapse
Affiliation(s)
- Constanze Keck
- Institut für Organische Chemie
- Universität Tübingen
- 72076 Tübingen
- Germany
| | | | | |
Collapse
|
11
|
Bluer KR, Laperriere LE, Pujol A, Yruegas S, Adiraju VAK, Martin CD. Coordination and Ring Expansion of 1,2-Dipolar Molecules with 9-Phenyl-9-borafluorene. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00497] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Kristen R. Bluer
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, Texas 76798, United States
| | - Leif E. Laperriere
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, Texas 76798, United States
| | - Alba Pujol
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, Texas 76798, United States
| | - Sam Yruegas
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, Texas 76798, United States
| | - Venkata A. K. Adiraju
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, Texas 76798, United States
| | - Caleb D. Martin
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, Texas 76798, United States
| |
Collapse
|
12
|
Yruegas S, Barnard JH, Al-Furaiji K, Dutton JL, Wilson DJD, Martin CD. Boraphosphaalkene Synthesis via Phosphaalkyne Insertion into 9-Borafluorene. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00248] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Sam Yruegas
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco Texas 76798-7343, United States
| | - Jonathan H. Barnard
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco Texas 76798-7343, United States
| | - Khalidah Al-Furaiji
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Jason L. Dutton
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - David J. D. Wilson
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Caleb D. Martin
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco Texas 76798-7343, United States
| |
Collapse
|
13
|
Hahn J, Biswas S, Maichle-Mössmer C, Schrenk C, Schnepf A, Bettinger HF. Borenium and boronium ions of 5,6-dihydro-dibenzo[c,e][1,2]azaborinine and the reaction with non-nucleophilic base: trapping of a dimer and a trimer of BN-phenanthryne by 4,4′-di-tert-butyl-2,2′-bipyridine. PURE APPL CHEM 2018. [DOI: 10.1515/pac-2017-1103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
6-Chloro-5,6-dihydro-dibenzo[c,e][1,2]azaborinine (1) reacts with pyridine derivatives to borenium or boronium ions. The boronium ion obtained from reaction with an excess of pyridine could be characterized structurally and transforms into the borenium ion in solution. The reaction of 1 with 2,2′-bipyridine (a) and derivatives (b: 6,6′-dimethyl; c: 4,4′-di-tert-butyl) results in spirocyclic boronium ions 8a–c of which 8b could be characterized by X-ray crystallography. Despite the chelate effect, the spirocyclic boronium ions readily undergo hydrolysis or alcoholysis. Treatment of the spirocyclic boronium ion 8c with potassium hexamethyl disilazide (KHMDS) results in neutral products that are monomers, dimers, or trimers of dibenzo[c,e][1,2]azaborinine (“BN-phenanthryne”) trapped with 4,4′-di-tert-butyl-2,2′-bipyridine by formation of B–C, B–N, or dative B–N bonds, indicative of deprotonation of NH and CH bonds of the boronium ion by KHMDS.
Collapse
Affiliation(s)
- Jennifer Hahn
- Institut für Organische Chemie , Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany
| | - Sunanda Biswas
- Institut für Organische Chemie , Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany
| | - Cäcilia Maichle-Mössmer
- Institut für Anorganische Chemie , Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany
| | - Claudio Schrenk
- Institut für Anorganische Chemie , Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany
| | - Andreas Schnepf
- Institut für Anorganische Chemie , Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany
| | - Holger F. Bettinger
- Institut für Organische Chemie , Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany
| |
Collapse
|
14
|
Yruegas S, Martinez JJ, Martin CD. Intermolecular insertion reactions of azides into 9-borafluorenes to generate 9,10-B,N-phenanthrenes. Chem Commun (Camb) 2018; 54:6808-6811. [DOI: 10.1039/c8cc01529e] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The reactions of 9-borafluorenes with organic azides result in either the insertion of the α-nitrogen and elimination of N2 or the insertion of the γ-nitrogen to generate the corresponding phenanthrene analogues with boron and nitrogen in the 9- and 10-positions, respectively.
Collapse
Affiliation(s)
- Sam Yruegas
- Baylor University
- Department of Chemistry and Biochemistry
- Waco
- USA
| | | | - Caleb D. Martin
- Baylor University
- Department of Chemistry and Biochemistry
- Waco
- USA
| |
Collapse
|
15
|
von Grotthuss E, John A, Kaese T, Wagner M. Doping Polycyclic Aromatics with Boron for Superior Performance in Materials Science and Catalysis. ASIAN J ORG CHEM 2017. [DOI: 10.1002/ajoc.201700495] [Citation(s) in RCA: 207] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Esther von Grotthuss
- Institut für Anorganische Chemie; Goethe-Universität Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt a. M. Germany
| | - Alexandra John
- Institut für Anorganische Chemie; Goethe-Universität Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt a. M. Germany
| | - Thomas Kaese
- Institut für Anorganische Chemie; Goethe-Universität Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt a. M. Germany
| | - Matthias Wagner
- Institut für Anorganische Chemie; Goethe-Universität Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt a. M. Germany
| |
Collapse
|
16
|
Edel K, Fink RF, Bettinger HF. Isomerization and fragmentation pathways of 1,2-azaborine. J Comput Chem 2015; 37:110-6. [PMID: 26418051 DOI: 10.1002/jcc.24189] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 07/28/2015] [Accepted: 07/30/2015] [Indexed: 11/11/2022]
Abstract
The generation of 1,2-azaborine (4), the BN-analogue of ortho-benzyne, was recently achieved by elimination of tert-butyldimethylchlorosilane under the conditions of flash vacuum pyrolysis. The present investigation identifies by computational means pathways for the thermal isomerization and fragmentation of 1,2-azaborine. The computations were performed using single reference (hybrid/density functional, second order Møller-Plesset perturbation, and coupled cluster theories) as well as multiconfiguration methods (complete active space SCF based second order perturbation theory, multireference configuration interaction, and multiconfiguration coupled electron pair approximation) with basis sets up to polarized triple-ζ quality. The 1,2-azaborine is, despite the distortion of its molecular structure, the most stable C4H4BN isomer investigated. The formation of BN-endiyne isomers is highly unfavorable as the identified pathways involve barriers close to 80 kcal mol(-1). The concerted fragmentation to ethyne and 2-aza-3-bora-butadiyne even has a barrier close to 120 kcal mol(-1). The fragmentation of BN-enediynes has energetic requirements similar to enediynes.
Collapse
Affiliation(s)
- Klara Edel
- Institut Für Organische Chemie, Universität Tübingen, Auf Der Morgenstelle 18, Tübingen, 72076, Germany
| | - Reinhold F Fink
- Institut Für Physikalische Und Theoretische Chemie, Universität Tübingen, Auf Der Morgenstelle 18, Tübingen, 72076, Germany
| | - Holger F Bettinger
- Institut Für Organische Chemie, Universität Tübingen, Auf Der Morgenstelle 18, Tübingen, 72076, Germany
| |
Collapse
|
17
|
Braunschweig H, Celik MA, Hupp F, Krummenacher I, Mailänder L. Formation of BN Isosteres of Azo Dyes by Ring Expansion of Boroles with Azides. Angew Chem Int Ed Engl 2015; 54:6347-51. [PMID: 25808881 DOI: 10.1002/anie.201500970] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Indexed: 11/08/2022]
Abstract
Herein, we present the results of our investigations on the effect of ortho substitution of aryl azides on the ring-expansion reaction of boroles, five-membered unsaturated boron heterocycles. These studies led to the isolation of the first 1,2-azaborinine-substituted azo dyes, which are bright yellow solids. One of the derivatives, (E)-2-mesityl-1-(mesityldiazenyl)-3,4,5,6-tetraphenyl-1,2-azaborinine, was found to be unstable in solution and to transform through a Jacobsen-like reaction into an indazole and 1-hydro-1,2-azaborinine. DFT calculations were performed to shed light on possible mechanisms to rationalize the unexpected azo-azaborinine formation and to draw conclusions about the role played by the ortho substituents in the reaction.
Collapse
Affiliation(s)
- Holger Braunschweig
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.ak-braunschweig.chemie.uni-wuerzburg.de/.
| | - Mehmet Ali Celik
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.ak-braunschweig.chemie.uni-wuerzburg.de/
| | - Florian Hupp
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.ak-braunschweig.chemie.uni-wuerzburg.de/
| | - Ivo Krummenacher
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.ak-braunschweig.chemie.uni-wuerzburg.de/
| | - Lisa Mailänder
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany) http://www-anorganik.ak-braunschweig.chemie.uni-wuerzburg.de/
| |
Collapse
|
18
|
Braunschweig H, Celik MA, Hupp F, Krummenacher I, Mailänder L. Synthese BN-isosterer Verbindungen von Azofarbstoffen durch Ringerweiterung von Borolen mit Aziden. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201500970] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|