1
|
Zarkina VG, Nichol GS, Cowley MJ. Heavy Heterodendralenes: Structure and Reactivity of Phosphabora[3]dendralenes. J Am Chem Soc 2024. [PMID: 39141774 DOI: 10.1021/jacs.4c07850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2024]
Abstract
The incorporation of phosphorus and boron into [3]dendralenes provides access to heavy heterodendralenes, a new class of main-group precursor to "doped" polycyclic hydrocarbons. [n]Dendralenes are a core class of unsaturated hydrocarbons built from geminally connected polyenes; the resulting arrangement of conjugated C═C bonds enables [n]dendralenes to undergo reactions that allow rapid access to complex polycyclic compounds. The increasing technological and synthetic importance of main-group-containing polycyclic hydrocarbons and their analogues makes new routes to access such systems highly attractive. Here we report the preparation of the first heavy heterodendralenes in the form of phosphorus- and boron-containing [3]dendralenes, prepared by a ring-opening reaction of a 1,2-phosphaborete. We reveal the electronic effect of P/B incorporation and demonstrate that, like their hydrocarbon analogues, phosphabora[3]dendralenes undergo diene-transmissive cycloaddition chemistry.
Collapse
Affiliation(s)
- Vesela G Zarkina
- 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
| |
Collapse
|
2
|
Tra BYE, Molino A, Hollister KK, Sarkar SK, Dickie DA, Wilson DJD, Gilliard RJ. Mono- and Bis-Phosphine Promoted Incorporation of Boron, Nitrogen, and Phosphorus into Heterocycles via Staudinger Reactions of Borafluorene Azides. Inorg Chem 2024; 63:11604-11615. [PMID: 38864676 DOI: 10.1021/acs.inorgchem.4c00854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
We report the synthesis and characterization of a series of BNP-incorporated borafluorenate heterocycles formed via thermolysis reactions of pyridylphosphine and bis(phosphine)-coordinated borafluorene azides. The use of diphenyl-2-pyridylphosphine (PyPh2P), trans-1,2-bis(diphenylphosphino)ethylene (Ph2P(H)C═C(H)PPh2), and bis(diphenylphosphino)methane (Ph2PC(H2)PPh2) as stabilizing ligands resulted in Staudinger reactions to form complex heterocycles with four- (BN2P, BNPC, P2N2) and five-membered (BNP2C and BN2PC) rings, which were successfully isolated and fully characterized by multinuclear NMR and X-ray crystallography. However, when bis(diphenylphosphino)benzene (Ph2P-Ph-PPh2) was used as the ligand in a reaction with 9-bromo-9-borafluorene (BF-Br), due to the close proximity of the donor P atoms, the diphosphine-stabilized borafluoronium ion with an unusual borafluorene dibromide anion was formed. Reaction of the borafluoronium ion with trimethylsilyl azide left the cation intact, and the dibromide anion was substituted by a diazide. Density functional theory calculations were used to provide mechanistic insight into the formation of these new boracyclic compounds. This work highlights a new method in which donor phosphine ligands may be used to promote dimerization, cyclization, and ring contraction reactions to produce boracycles via Staudinger reactions.
Collapse
Affiliation(s)
- Bi Youan E Tra
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| | - Andrew Molino
- Department of Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne 3086, Victoria, Australia
| | - Kimberly K Hollister
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| | - Samir Kumar Sarkar
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - David J D Wilson
- Department of Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne 3086, Victoria, Australia
| | - Robert J Gilliard
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| |
Collapse
|
3
|
Wen M, Medel R, Zasimov PV, Müller C, Riedel S. B[double bond, length as m-dash]P double bonds relieved from steric encumbrance: matrix-isolation infrared spectroscopy of the phosphaborene F 2B-P[double bond, length as m-dash]BF and the triradical B[double bond, length as m-dash]PF 3. Chem Sci 2024; 15:8045-8051. [PMID: 38817554 PMCID: PMC11134404 DOI: 10.1039/d4sc01913j] [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: 03/21/2024] [Accepted: 04/28/2024] [Indexed: 06/01/2024] Open
Abstract
Free phosphaborenes have a labile boron-phosphorus double bond and therefore require extensive steric shielding by bulky substituents to prevent isomerisation and oligomerisation. In the present work, the small free phosphaborene F2B-P[double bond, length as m-dash]BF was isolated by matrix-isolation techniques and was characterised by infrared spectroscopy in conjunction with quantum-chemical methods. In contrast to its sterically hindered relatives, this small phosphaborene exhibits an acute BPB angle of 83° at the CCSD(T) level. An alternative orbital structure for the B[double bond, length as m-dash]P double bond is found in the triradical B[double bond, length as m-dash]PF3, the direct adduct of laser-ablated atomic B and PF3. The single-bonded isomer F2B-PF and the dimer F3P-B[triple bond, length as m-dash]B-PF3 are also tentatively assigned.
Collapse
Affiliation(s)
- Mei Wen
- Freie Universität Berlin, Institut für Chemie und Biochemie - Anorganische Chemie Fabeckstraße 34/36 14195 Berlin Germany
| | - Robert Medel
- Freie Universität Berlin, Institut für Chemie und Biochemie - Anorganische Chemie Fabeckstraße 34/36 14195 Berlin Germany
| | - Pavel V Zasimov
- Freie Universität Berlin, Institut für Chemie und Biochemie - Anorganische Chemie Fabeckstraße 34/36 14195 Berlin Germany
| | - Carsten Müller
- Freie Universität Berlin, Institut für Chemie und Biochemie - Anorganische Chemie Fabeckstraße 34/36 14195 Berlin Germany
| | - Sebastian Riedel
- Freie Universität Berlin, Institut für Chemie und Biochemie - Anorganische Chemie Fabeckstraße 34/36 14195 Berlin Germany
| |
Collapse
|
4
|
Li Y, Tamizmani M, Akram MO, Martin CD. Carborane-arene fused boracyclic analogues of polycyclic aromatic hydrocarbons accessed by intramolecular borylation. Chem Sci 2024; 15:7568-7575. [PMID: 38784749 PMCID: PMC11110167 DOI: 10.1039/d4sc00990h] [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: 02/10/2024] [Accepted: 04/13/2024] [Indexed: 05/25/2024] Open
Abstract
Arenes are 2D aromatics while dicarbadodecaborane clusters are branded as 3D aromatic molecules. In this work we prepare molecules that feature fused 2D/3D aromatic systems that represent boron-doped analogues of polycyclic aromatic hydrocarbons. The electron withdrawing nature of the ortho-carborane substituent enables swift arene borylation on boron bromide or hydride precursors to furnish five- and six-membered boracycles in conjugation with the arene. The mechanism was modeled by DFT computations implying a concerted transition state and analyzing the photophysical properties revealed high quantum yields in the six-membered systems.
Collapse
Affiliation(s)
- Yijie Li
- Baylor University, Department of Chemistry and Biochemistry One Bear Place #97348 Waco TX 76798 USA
| | - Masilamani Tamizmani
- Baylor University, Department of Chemistry and Biochemistry One Bear Place #97348 Waco TX 76798 USA
| | - Manjur O Akram
- Baylor University, Department of Chemistry and Biochemistry One Bear Place #97348 Waco TX 76798 USA
| | - Caleb D Martin
- Baylor University, Department of Chemistry and Biochemistry One Bear Place #97348 Waco TX 76798 USA
| |
Collapse
|
5
|
Hollister KK, Wentz KE, Gilliard RJ. Redox- and Charge-State Dependent Trends in 5, 6, and 7-Membered Boron Heterocycles: A Neutral Ligand Coordination Chemistry Approach to Boracyclic Cations, Anions, and Radicals. Acc Chem Res 2024; 57:1510-1522. [PMID: 38708938 DOI: 10.1021/acs.accounts.4c00096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2024]
Abstract
ConspectusBoron heterocycles represent an important subset of heteroatom-incorporated rings, attracting attention from organic, inorganic, and materials chemists. The empty pz orbital at the boron center makes them stand out as quintessential Lewis acidic molecules, also serving as a means to modulate electronic structure and photophysical properties in a facile manner. As boracycles are ripe for extensive functionalization, they are used in catalysis, chemical biology, materials science, and continue to be explored as chemical synthons for conjugated materials and reagents. Neutral boron(III)-incorporated polycyclic molecules are some of the most studied types of boracycles, and understanding their redox transformations is important for applications relying on electron transfer and charge transport. While relevant redox species can often be electrochemically observed, it remains challenging to isolate and characterize boracycles where the boron center and/or polycyclic skeleton have been chemically reduced.We describe our recent work isolating 5-, 6-, and 7-membered boracyclic radicals, anions, and cations, focusing on stabilization strategies, ligand-mediated bonding situations, and reactivity. We present a versatile neutral ligand coordination chemistry approach that permits the transformation of boracycles from potent electrophiles to powerful nucleophilic heterocycles that facilitate diverse electron transfer and bond activation chemistry. Although there are a wide range of suitable stabilizing ligands, we have employed both diamino-N-heterocyclic carbenes (NHCs) and cyclic(alkyl)(amino) carbenes (CAACs), which led to boracycles with tunable electronic structures and aromaticity trends. We highlight successful isolation of borafluorene radicals and demonstrate their reversible redox behavior, undergoing oxidation to the cation or reduction to the anion. The borafluorene anion is a chemical synthon that has been used to prepare boryl main-group and transition-metal bonds, luminescent oxabora-spirocycles, borafluorenate-crown ethers, and CO-releasing molecules via carbon dioxide activation. We expanded to 6-membered boracycles and characterized neutral bis(NHC-supported 9-boraphenanthrene)s and the corresponding bis(CAAC-stabilized 9-boraphenanthrene) biradical. We detail the interconvertible multiredox states of boraphenalene, where the boraphenalenyl radical, anion, and cation mimic the charge-states of the all-hydrocarbon analogue. Reactivity studies of the boraphenalenyl anion displayed unusual nucleophilic reactivity at multiple sites on the periphery of the boraphenalenyl tricyclic scaffold. Reduced borepins, 7-membered boron containing heterocycles, have also been isolated. We used a stepwise one-pot synthesis combining the halo-borepin precursor, CAAC, and KC8 to afford the monomeric borepin radicals and anions. The π-system was extended to contain two borepin rings fused in a pentacyclic scaffold, which permitted isolation of diborepin biradicals and a diborepin containing a dibora-quinone core.Our goal is to provide a guide explaining the current structure-function trends and isolation strategies for redox-active boron-incorporated polycyclic molecules to initiate the rational design and use of these types of compounds across a vast chemical space.
Collapse
Affiliation(s)
- Kimberly K Hollister
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| | - Kelsie E Wentz
- Department of Chemistry, Johns Hopkins University, Remson Hall, 3400 N Charles Street, Baltimore, Maryland 21218-2625, United States
| | - Robert J Gilliard
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| |
Collapse
|
6
|
Ramachandran MRK, Karwasara S, Zhu H, Schnakenburg G, Streubel R. Synthesis of tricyclic 1,4-dihydro-1,4-phosphagermines - trying to establish molecular fencing of reactive centers. Dalton Trans 2024; 53:7953-7957. [PMID: 38646810 DOI: 10.1039/d4dt00895b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Novel tricyclic 1,4-dihydro-1,4-phosphagermines (3a and 4a) were synthesised from Ge(NR2)2-bridged 1,3-imidazole-2-thione derivative 2a; all structures were crystallographically confirmed. In going from rather small alkyl substituents (Me, nBu) at the nitrogen centers of the 1,3-imidazole-2-thione units to sterically more demanding R = Mes and changing the employed Ge reagent from (R2N)2GeCl2 to R2NGeCl3 we achieved access to mixed functional bis(1,3-imidazole-2-thione)-substituted germanium derivative 2c. The latter was treated with MeLi and, subsequently, with PCl3 to yield a pentacyclic P,Ge-heterocycle (5); its formation was rationalized using DFT theoretical calculations.
Collapse
Affiliation(s)
- Mridhul R K Ramachandran
- Institut für Anorganische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Straße 1, 53121 Bonn, Germany.
| | - Surendar Karwasara
- Institut für Anorganische Chemie, University of Duisburg-Essen, Universitätsstr. 7, 45117 Essen, Germany
| | - Hui Zhu
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Gregor Schnakenburg
- Institut für Anorganische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Straße 1, 53121 Bonn, Germany.
| | - Rainer Streubel
- Institut für Anorganische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Straße 1, 53121 Bonn, Germany.
| |
Collapse
|
7
|
Bhunia M, Mohar JS, Sandoval-Pauker C, Fehn D, Yang ES, Gau M, Goicoechea J, Ozarowski A, Krzystek J, Telser J, Meyer K, Mindiola DJ. Softer Is Better for Titanium: Molecular Titanium Arsenido Anions Featuring Ti≡As Bonding and a Terminal Parent Arsinidene. J Am Chem Soc 2024; 146:3609-3614. [PMID: 38290427 DOI: 10.1021/jacs.3c12939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
We introduce the arsenido ligand onto the TiIV ion, yielding a remarkably covalent Ti≡As bond and the parent arsinidene Ti═AsH moiety. An anionic arsenido ligand is assembled via reductive decarbonylation involving the discrete TiII salt [K(cryptand)][(PN)2TiCl] (1) (cryptand = 222-Kryptofix) and Na(OCAs)(dioxane)1.5 in thf/toluene to produce the mixed alkali ate-complex [(PN)2Ti(As)]2(μ2-KNa(thf)2) (2) and the discrete salt [K(cryptand)][(PN)2Ti≡As] (3) featuring a terminal Ti≡As ligand. Protonation of 2 or 3 with various weak acids cleanly forms the parent arsinidene [(PN)2Ti═AsH] (4), which upon deprotonation with KCH2Ph in thf generates the more symmetric anionic arsenido [(PN)2Ti(As){μ2-K(thf)2}]2 (5). Experimental and computational studies suggest the pKa of 4 to be ∼23, and the bond orders in 2, 3, and 5 are all in the range of a Ti≡As triple bond, with decreasing bond order in 4.
Collapse
Affiliation(s)
- Mrinal Bhunia
- Department of Chemistry, University of Pennsylvania, 231 S 34th St, Philadelphia, Pennsylvania 19104, United States
| | - Jacob S Mohar
- Department of Chemistry, University of Pennsylvania, 231 S 34th St, Philadelphia, Pennsylvania 19104, United States
| | - Christian Sandoval-Pauker
- Department of Chemistry and Biochemistry, University of Texas at El Paso, El Paso, Texas 79968, United States
| | - Dominik Fehn
- Departments of Chemistry & Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen - Nürnberg (FAU), 91058 Erlangen, Germany
| | - Eric S Yang
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Michael Gau
- Department of Chemistry, University of Pennsylvania, 231 S 34th St, Philadelphia, Pennsylvania 19104, United States
| | - Jose Goicoechea
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Andrew Ozarowski
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - J Krzystek
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Joshua Telser
- Department of Biological, Physical and Health Sciences, Roosevelt University, Chicago, Illinois 60605, United States
| | - Karsten Meyer
- Departments of Chemistry & Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen - Nürnberg (FAU), 91058 Erlangen, Germany
| | - Daniel J Mindiola
- Department of Chemistry, University of Pennsylvania, 231 S 34th St, Philadelphia, Pennsylvania 19104, United States
| |
Collapse
|
8
|
Lu B, Zeng X. Phosphinidenes: Fundamental Properties and Reactivity. Chemistry 2023:e202303283. [PMID: 38108540 DOI: 10.1002/chem.202303283] [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: 10/07/2023] [Revised: 12/12/2023] [Accepted: 12/18/2023] [Indexed: 12/19/2023]
Abstract
Phosphinidenes are heavy congeners of nitrenes that have been broadly used as in situ reagents in synthetic phosphorus chemistry and also serve as versatile ligands in coordination with transition metals. However, the detection of free phosphinidenes is largely challenged by their high reactivity and also the lack of suitable synthetic methods, rendering the knowledge about the fundamental properties of this class of low-valent phosphorus compounds limited. Recently, an increasing number of free phosphinidenes bearing prototype structural and bonding properties have been prepared for the first time, thus enabling the exploration of their distinct reactivity from the nitrene analogues. This Concept article will discuss the experimental approaches for the generation of the highly unstable phosphinidenes and highlight their distinct reactivity from the nitrogen analogues so as to stimuate future studies about their potential applications in phosphorus chemistry.
Collapse
Affiliation(s)
- Bo Lu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, 200433, China
| | - Xiaoqing Zeng
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, 200433, China
| |
Collapse
|
9
|
Baradzenka AG, Vyboishchikov SF, Pilkington M, Nikonov GI. Base-Stabilized Phosphinidene Oxide, Imide and Sulfide. Chemistry 2023; 29:e202301842. [PMID: 37490421 DOI: 10.1002/chem.202301842] [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: 06/08/2023] [Revised: 07/20/2023] [Accepted: 07/24/2023] [Indexed: 07/27/2023]
Abstract
Oxidation of a base-stabilized phosphinidene (κ2 -NNP)P (12, NNP=phosphinoamidinate) with N2 O afforded a labile phosphinidene oxide (κ2 -NNP)P=O (16) which was characterized by NMR spectroscopy. Further oxidation of 16 by N2 O or reaction of 12 with two equivalents of pyridine oxide afforded the isolable dioxide (κ2 -NNP)PO2 which was characterized by NMR and SC XRD. Trapping of 16 with tolyl isocyanate resulted in P=O/N=C metathesis, eventually affording a urea-ligated phosphine (κ1 -NNP)P(NTol)2 C=O (17) The mechanism of this reaction was elucidated by DFT calculations. Reactions of phosphinidene 12 with azides generated transient imines (NNP)P=NR, which in the case of R=Tol underwent cycloaddition with tolyl Isocyanate to afford the urea product 17, and in the case of R=SiMe3 reacts with N3 SiMe3 via the addition of N-Si across the P=N bond affording, after the extrusion of dinitrogen, a P,N-heterocyclic compound. Both products of the reactions with azides have been fully characterized, both in solution and the solid-state. Finally, reaction of phosphinidene 12 with one equivalent of sulfur resulted in the isolation of the base-stabilized phosphinidene sulfide (κ2 -NNP)P=S that has also been fully characterized.
Collapse
Affiliation(s)
- Aliona G Baradzenka
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada
| | - Sergei F Vyboishchikov
- Institut de Química Computacional i Catàlisi and Departament de Química Universitat de Girona, Carrer Maria Aurèlia Capmany 69, 17003, Girona, Spain
| | - Melanie Pilkington
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada
| | - Georgii I Nikonov
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada
| |
Collapse
|
10
|
Sarkar SK, Hollister KK, Molino A, Obi AD, Deng CL, Tra BYE, Stewart BM, Dickie DA, Wilson DJD, Gilliard RJ. Bis(9-Boraphenanthrene) and Its Stable Biradical. J Am Chem Soc 2023; 145:21475-21482. [PMID: 37738168 DOI: 10.1021/jacs.3c07236] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/24/2023]
Abstract
Selective and site-specific boron-doping of polycyclic aromatic hydrocarbon frameworks often give rise to redox and/or photophysical properties that are not easily accessible with the analogous all-carbon systems. Herein, we report ligand-mediated control of boraphenanthrene closed- and open-shell electronic states, which has led to the first structurally characterized examples of neutral bis(9-boraphenanthrene) (2-3) and its corresponding biradical (4). Notably, compounds 2 and 3 show intramolecular charge transfer absorption from the 9-boraphenanthrene units to p-quinodimethane, exhibiting dual (red-shifted) emission in solution due to excited state conjugation enhancement (ESCE). Moreover, while boron-centered monoradicals are ubiquitous, biradical 4 represents a rare type of open-shell singlet compound with 95% biradical character, among the highest of any reported boron-based polycyclic species with two radical sites.
Collapse
Affiliation(s)
- Samir Kumar Sarkar
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Kimberly K Hollister
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Andrew Molino
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086 Victoria, Australia
| | - Akachukwu D Obi
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Chun-Lin Deng
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Bi Youan E Tra
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Brennan M Stewart
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - David J D Wilson
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086 Victoria, Australia
| | - Robert J Gilliard
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| |
Collapse
|
11
|
Tra BYE, Molino A, Hollister KK, Sarkar SK, Dickie DA, Wilson DJD, Gilliard RJ. Photochemically and Thermally Generated BN-Doped Borafluorenate Heterocycles via Intramolecular Staudinger-Type Reactions. Inorg Chem 2023; 62:15809-15818. [PMID: 37715684 DOI: 10.1021/acs.inorgchem.3c02284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/18/2023]
Abstract
A series of BN-incorporated borafluorenate heterocycles, bis(borafluorene-phosphinimine)s (11-15), have been formed via intramolecular Staudinger-type reactions. The reactions were promoted by light or heat using monodentate phosphine-stabilized 9-azido-9-borafluorenes (R3P-BF-N3; 6-10) and involve the release of dinitrogen (N2), migration of phosphine from boron to nitrogen, and oxidation of the phosphorus center (PIII to PV). Density functional theory (DFT) calculations provide mechanistic insight into the formation of these compounds. Compounds 11-15 are blue emissive in the solution and solid states with absolute quantum yields (ΦF) ranging from 12 to 68%.
Collapse
Affiliation(s)
- Bi Youan E Tra
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| | - Andrew Molino
- Department of Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086, Victoria, Australia
| | - Kimberly K Hollister
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| | - Samir Kumar Sarkar
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - David J D Wilson
- Department of Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086, Victoria, Australia
| | - Robert J Gilliard
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, Massachusetts 02139-4307, United States
| |
Collapse
|
12
|
Akram MO, Martin CD, Dutton JL. The Effect of Carborane Substituents on the Lewis Acidity of Boranes. Inorg Chem 2023; 62:13495-13504. [PMID: 37560972 DOI: 10.1021/acs.inorgchem.3c01872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
The Lewis acidity of primary, secondary, and tertiary boranes with phenyl, pentafluorophenyl, and all three isomers of the C-substituted icosahedral carboranes (ortho, meta, and para) was investigated by computing their fluoride, hydride, and ammonia affinities as well as their global electrophilicity indices and LUMO energies. From these calculations, it was determined that the substituent effects on the Lewis acidity of these boranes follow the trend of ortho-carborane > meta-carborane > para-carborane > C6F5 > C6H5.
Collapse
Affiliation(s)
- Manjur O Akram
- Baylor University, Department of Chemistry and Biochemistry, One Bear Place #97348, Waco, Texas 76798, United States
| | - Caleb D Martin
- Baylor University, Department of Chemistry and Biochemistry, One Bear Place #97348, Waco, Texas 76798, United States
| | - Jason L Dutton
- La Trobe University, Department of Chemistry, La Trobe Institute for Molecular Science, Melbourne, Victoria 3086,Australia
| |
Collapse
|
13
|
Nees S, Wellnitz T, Dankert F, Härterich M, Dotzauer S, Feldt M, Braunschweig H, Hering-Junghans C. On the Reactivity of Phosphaalumenes towards C-C Multiple Bonds. Angew Chem Int Ed Engl 2023; 62:e202215838. [PMID: 36516342 DOI: 10.1002/anie.202215838] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/11/2022] [Accepted: 12/14/2022] [Indexed: 12/15/2022]
Abstract
Heterocycles containing group 13 and 15 elements such as borazines are an integral part of organic, biomedical and materials chemistry. Surprisingly, heterocycles containing P and Al are rare. We have now utilized phosphaalumenes in reactions with alkynes, alkenes and conjugated double bond systems. With sterically demanding alkynes 1,2-phosphaalumetes were afforded, whereas the reaction with HCCH or HCCSiMe3 gave 1,4-phosphaaluminabarrelenes. Using styrene saturated 1,2-phosphaalumates were formed, which reacted further with additional styrene to give different regio-isomers of 1,4-aluminaphosphorinanes. Using ethylene, a 1,4-aluminaphosphorinane is obtained, while with 1,3-butadiene a bicyclic system containing an aluminacyclopentane and a phosphirane unit was synthesized. The experimental work is supported by theoretical studies to shed light on the mechanism governing the formation of these heterocycles.
Collapse
Affiliation(s)
- Samuel Nees
- 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
| | - Tim Wellnitz
- 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.,Leibniz-Institut für Katalyse e.V. (LIKAT), Albert-Einstein-Straße 3a, 18059, Rostock, Germany
| | - Fabian Dankert
- Leibniz-Institut für Katalyse e.V. (LIKAT), Albert-Einstein-Straße 3a, 18059, Rostock, Germany
| | - Marcel Härterich
- 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
| | - Simon Dotzauer
- 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
| | - Milica Feldt
- Leibniz-Institut für Katalyse e.V. (LIKAT), Albert-Einstein-Straße 3a, 18059, Rostock, 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
| | | |
Collapse
|
14
|
Wentz KE, Molino A, Freeman LA, Dickie DA, Wilson DJD, Gilliard RJ. Approaching Dianionic Tetraoxadiborecine Macrocycles: 10-Membered Bora-Crown Ethers Incorporating Borafluorenate Units. Angew Chem Int Ed Engl 2023; 62:e202215772. [PMID: 36437238 DOI: 10.1002/anie.202215772] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/24/2022] [Accepted: 11/25/2022] [Indexed: 11/29/2022]
Abstract
The addition of non-benzenoid quinones, acenapthenequinone or aceanthrenequinone, to the 9-carbene-9-borafluorene monoanion (1) affords the first examples of dianionic 10-membered bora-crown ethers (2-5), which are characterized by multi-nuclear NMR spectroscopy (1 H, 13 C, 11 B), X-ray crystallography, elemental analysis, and UV/Vis spectroscopy. These tetraoxadiborecines have distinct absorption profiles based on the positioning of the alkali metal cations. When compound 4, which has a vacant C4 B2 O4 cavity, is reacted with sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, a color change from purple to orange serves as a visual indicator of metal binding to the central ring, whereby the Na+ ion coordinates to four oxygen atoms. A detailed theoretical analysis of the calculated reaction energetics is provided to gain insight into the reaction mechanism for the formation of 2-5. These data, and the electronic structures of proposed intermediates, indicate that the reaction proceeds via a boron enolate intermediate.
Collapse
Affiliation(s)
- Kelsie E Wentz
- Department of Chemistry, University of Virginia, 409 McCormick Rd./PO Box 400319, 22904, Charlottesville, VA, USA
| | - Andrew Molino
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, 3086, Melbourne, Victoria, Australia
| | - Lucas A Freeman
- Department of Chemistry, University of Virginia, 409 McCormick Rd./PO Box 400319, 22904, Charlottesville, VA, USA
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, 409 McCormick Rd./PO Box 400319, 22904, Charlottesville, VA, USA
| | - David J D Wilson
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, 3086, Melbourne, Victoria, Australia
| | - Robert J Gilliard
- Department of Chemistry, University of Virginia, 409 McCormick Rd./PO Box 400319, 22904, Charlottesville, VA, USA
| |
Collapse
|
15
|
Li Y, Shen YH, Esper AM, Tidwell JR, Veige AS, Martin CD. Probing borafluorene B-C bond insertion with gold acetylide and azide. Dalton Trans 2023; 52:668-674. [PMID: 36537567 DOI: 10.1039/d2dt03672j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The reaction of Ph3PAuN3 with 9-Ph-9-borafluorene resulted in complexation of the azide to boron while a gold acetylide reacted with 9-Ph-9-borafluorene to insert the acetylide carbon to access a six-membered boracycle with an exocyclic double bond.
Collapse
Affiliation(s)
- Yijie Li
- Baylor University, Department of Chemistry and Biochemistry, One Bear Place #97348, Waco, TX 76798, USA.
| | - Yu-Hsuan Shen
- University of Florida, Department of Chemistry, Center for Catalysis, Gainesville, FL 32611, USA
| | - Alec M Esper
- University of Florida, Department of Chemistry, Center for Catalysis, Gainesville, FL 32611, USA
| | - John R Tidwell
- Baylor University, Department of Chemistry and Biochemistry, One Bear Place #97348, Waco, TX 76798, USA.
| | - Adam S Veige
- University of Florida, Department of Chemistry, Center for Catalysis, Gainesville, FL 32611, USA
| | - Caleb D Martin
- Baylor University, Department of Chemistry and Biochemistry, One Bear Place #97348, Waco, TX 76798, USA.
| |
Collapse
|
16
|
Li J, Lu Z, Liu LL. A Free Phosphaborene Stable at Room Temperature. J Am Chem Soc 2022; 144:23691-23697. [PMID: 36520955 DOI: 10.1021/jacs.2c11878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Free phosphaborenes (R-P═B-R) are PB analogues of alkynes, and their isolation is a long-sought-after goal. Herein, we demonstrate that the combination of a π-donating and a π-accepting substituent with bulky flanking arene rings enables the isolation of a crystalline free phosphaborene 5 at room temperature. This electron push-pull cooperation, combined with the kinetic protection, hinders its inherent tendency to oligomerize. This species features a PB double bond consisting of a conventional σ bond and a delocalized π bond. The lone pair of electrons at P slightly contributes to the PB bonding. Preliminary reactivity studies show that 5 undergoes facile (cyclo)addition reactions with p-methyl benzaldehyde, p-fluoroacetophenone, and carbon disulfide, the last of which results in facile PB double bond cleavage. Our strategy has a significant impact on the future synthesis of ambiphilic heterodiatomic multiply bonded main group species.
Collapse
Affiliation(s)
- Jiancheng Li
- Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Zhihao Lu
- Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Liu Leo Liu
- Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
| |
Collapse
|
17
|
Senthil S, Kwon S, Fehn D, Im H, Gau MR, Carroll PJ, Baik MH, Meyer K, Mindiola DJ. Metal-Ligand Cooperativity to Assemble a Neutral and Terminal Niobium Phosphorus Triple Bond (Nb≡P). Angew Chem Int Ed Engl 2022; 61:e202212488. [PMID: 36195827 DOI: 10.1002/anie.202212488] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Indexed: 11/06/2022]
Abstract
Decarbonylation along with P-atom transfer from the phosphaethynolate anion, PCO- , to the NbIV complex [(PNP)NbCl2 (Nt BuAr)] (1) (PNP=N[2-Pi Pr2 -4-methylphenyl]2 - ; Ar=3,5-Me2 C6 H3 ) results in its coupling with one of the phosphine arms of the pincer ligand to produce a phosphanylidene phosphorane complex [(PNPP)NbCl(Nt BuAr)] (2). Reduction of 2 with CoCp*2 cleaves the P-P bond to form the first neutral and terminal phosphido complex of a group 5 transition metal, namely, [(PNP)Nb≡P(Nt BuAr)] (3). Theoretical studies have been used to understand both the coupling of the P-atom and the reductive cleavage of the P-P bond. Reaction of 3 with a two-electron oxidant such as ethylene sulfide results in a diamagnetic sulfido complex having a P-P coupled ligand, namely [(PNPP)Nb=S(Nt BuAr)] (4).
Collapse
Affiliation(s)
- Shuruthi Senthil
- Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA
| | - Seongyeon Kwon
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Dominik Fehn
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058, Erlangen, Germany
| | - Hoyoung Im
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Michael R Gau
- Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA
| | - Patrick J Carroll
- Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA
| | - Mu-Hyun Baik
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Karsten Meyer
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058, Erlangen, Germany
| | - Daniel J Mindiola
- Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA
| |
Collapse
|
18
|
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
|
19
|
Zhang C, Wang J, Lin Z, Ye Q. Synthesis, Characterization, and Properties of Three-Dimensional Analogues of 9-Borafluorenes. Inorg Chem 2022; 61:18275-18284. [DOI: 10.1021/acs.inorgchem.2c03111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Chonghe Zhang
- Department of Chemistry, Southern University of Science and Technology, 518055 Shenzhen, P. R. China
| | - Junyi Wang
- Department of Chemistry, Southern University of Science and Technology, 518055 Shenzhen, P. R. China
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, 999077 Kowloon, Hong Kong
| | - Zhenyang Lin
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, 999077 Kowloon, Hong Kong
| | - Qing Ye
- 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
|
20
|
Wentz KE, Molino A, Freeman LA, Dickie DA, Wilson DJD, Gilliard RJ. Systematic Electronic and Structural Studies of 9-Carbene-9-Borafluorene Monoanions and Transformations into Luminescent Boron Spirocycles. Inorg Chem 2022; 61:17049-17058. [PMID: 36259945 DOI: 10.1021/acs.inorgchem.2c01945] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The impact of the exact spatial arrangement of the alkali metal on the electronic properties of 9-carbene-9-borafluorene monoanions is assessed, and a series of [K][9-CAAC-9-borafluorene] complexes (1-4) have been isolated (CAAC = cyclic(alkyl)(amino) carbene, (2,6-diisopropylphenyl)-4,4-diethyl-2,2-dimethyl-pyrrolidin-5-ylidene). Compound 1, which contains [B]-K(THF)3 interactions, is compared to charge-separated 2-4, which were prepared by capturing the potassium cations with 18-crown-6, 2.2.2-cryptand, or 1,10-phenanthroline. Notably, the 11B NMR spectra of charge-separated borafluorene monoanions 2-4 show distinct low-field signatures compared to 1. Theoretical calculations indicate that charge separation may be exploited to influence the nucleophilic and electron transfer properties of 9-carbene-9-borafluorene monoanions. When [K(2.2.2-cryptand)][9-CAAC-9-borafluorene] (3) is reacted with 9,10-phenanthrenequinone and 1,10-phenanthroline-5,6-dione, the carbene ligand is displaced, and new air-stable R2BO2 spirocycles are formed (5 and 6, respectively). Remarkably, compounds 5 and 6 display fluorescence under UV light in both the solid and solution phases with quantum yields of up to 20%. In addition, a drastic red-shift in the emission color is observed in 6 because of the presence of the nitrogen atoms on the phenanthroline moiety. Mechanistic insights into the formation of these spirocycles are also described based on density functional theory calculations.
Collapse
Affiliation(s)
- Kelsie E Wentz
- Department of Chemistry, University of Virginia, Charlottesville 22904, Virginia, United States
| | - Andrew Molino
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne 3086, Victoria, Australia
| | - Lucas A Freeman
- Department of Chemistry, University of Virginia, Charlottesville 22904, Virginia, United States
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, Charlottesville 22904, Virginia, United States
| | - David J D Wilson
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne 3086, Victoria, Australia
| | - Robert J Gilliard
- Department of Chemistry, University of Virginia, Charlottesville 22904, Virginia, United States
| |
Collapse
|
21
|
Koner A, Morgenstern B, Andrada DM. Metathesis Reactions of a NHC‐Stabilized Phosphaborene. Angew Chem Int Ed Engl 2022; 61:e202203345. [PMID: 35583052 PMCID: PMC9401048 DOI: 10.1002/anie.202203345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Indexed: 11/25/2022]
Abstract
The BP unsaturated unit is a very attractive functional group as it provides novel reactivity and unique physical properties. Nonetheless, applications remain limited so far due to the bulky nature of B/P‐protecting groups, required to prevent oligomerization. Herein, we report the synthesis and isolation of a N‐heterocyclic carbene (NHC)‐stabilized phosphaborene, bearing a trimethylsilyl (TMS) functionality at the P‐terminal, as a room‐temperature‐stable crystalline solid accessible via facile NHC‐induced trimethylsilyl chloride (TMSCl) elimination from its phosphinoborane precursor. This phosphaborene compound, bearing a genuine B=P bond, exhibits a remarkable ability for undergoing P‐centre metathesis reactions, which allows the isolation of a series of unprecedented phosphaborenes. X‐ray crystallographic analysis, UV/Vis spectroscopy, and DFT calculations provide insights into the B=P bonding situation.
Collapse
Affiliation(s)
- Abhishek Koner
- Faculty of Natural Sciences and Technology Department of Chemistry Saarland University Campus C4.1 66123 Saarbrücken Germany
| | - Bernd Morgenstern
- Faculty of Natural Sciences and Technology Department of Chemistry Saarland University Campus C4.1 66123 Saarbrücken Germany
| | - Diego M. Andrada
- Faculty of Natural Sciences and Technology Department of Chemistry Saarland University Campus C4.1 66123 Saarbrücken Germany
| |
Collapse
|
22
|
Li J, Mei Y, Liu LL. An Isolable Phosphaborene Stabilized by an Intramolecular Lewis Base. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200368] [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)
- Jiancheng Li
- Southern University of Science and Technology Chemistry CHINA
| | - Yanbo Mei
- Southern University of Science and Technology Chemistry CHINA
| | - Liu Leo Liu
- Southern University of Science and Technology Chemistry 1088 Xueyuandadao 518055 Shenzhen CHINA
| |
Collapse
|
23
|
Akram MO, Tidwell JR, Dutton JL, Wilson DJD, Molino A, Martin CD. Accessing Boron-Doped Pentaphene Analogues from 12-Boradibenzofluorene. Inorg Chem 2022; 61:9595-9604. [PMID: 35696381 DOI: 10.1021/acs.inorgchem.2c00930] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Borole-doped polycyclic aromatic hydrocarbons (PAHs) have garnered attention in recent years due to their attractive photophysical properties and potential utility in electronic devices. In this work, a borole-doped PAH, 12-boradibenzofluorene, is synthesized and formal intermolecular nitrene and oxygen atom insertion reactions were employed to access 1,2-azaborine- and 1,2-oxaborine-containing analogues of the carbonaceous PAH pentaphene. Iodosobenzene is established as a versatile reagent for oxygen atom insertion reactions into a variety of borole species to access 1,2-oxaborine systems.
Collapse
Affiliation(s)
- Manjur O Akram
- 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
| | - Jason L Dutton
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne 3086, Victoria, Australia
| | - David J D Wilson
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne 3086, Victoria, Australia
| | - Andrew Molino
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne 3086, Victoria, Australia
| | - Caleb D Martin
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| |
Collapse
|
24
|
Koner A, Morgenstern B, Andrada DM. Metathese Reaktionen eines NHC‐stabilisierten Phosphaborens. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Abhishek Koner
- Faculty of Natural Sciences and Technology Department of Chemistry Saarland University Campus C4.1 66123 Saarbrücken Deutschland
| | - Bernd Morgenstern
- Faculty of Natural Sciences and Technology Department of Chemistry Saarland University Campus C4.1 66123 Saarbrücken Deutschland
| | - Diego M. Andrada
- Faculty of Natural Sciences and Technology Department of Chemistry Saarland University Campus C4.1 66123 Saarbrücken Deutschland
| |
Collapse
|
25
|
|
26
|
Sharma MK, Dhawan P, Helling C, Wölper C, Schulz S. Bis‐Phosphaketenes LM(PCO)
2
(M=Ga, In): A New Class of Reactive Group 13 Metal‐Phosphorus Compounds. Chemistry 2022; 28:e202200444. [PMID: 35226777 PMCID: PMC9314960 DOI: 10.1002/chem.202200444] [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: 02/02/2022] [Indexed: 11/11/2022]
Abstract
Phosphaketenes are versatile reagents in organophosphorus chemistry. We herein report on the synthesis of novel bis‐phosphaketenes, LM(PCO)2 (M=Ga 2 a, In 2 b; L=HC[C(Me)N(Ar)]2; Ar=2,6‐i‐Pr2C6H3) by salt metathesis reactions and their reactions with LGa to metallaphosphenes LGa(OCP)PML (M=Ga 3 a, In 3 b). 3 b represents the first compound with significant In−P π‐bonding contribution as was confirmed by DFT calculations. Compounds 3 a and 3 b selectively activate the N−H and O−H bonds of aniline and phenol at the Ga−P bond and both reactions proceed with a rearrangement of the phosphaethynolate group from Ga−OCP to M−PCO bonding. Compounds 2–5 are fully characterized by heteronuclear (1H, 13C{1H}, 31P{1H}) NMR and IR spectroscopy, elemental analysis, and single crystal X‐ray diffraction (sc‐XRD).
Collapse
Affiliation(s)
- Mahendra K. Sharma
- Institute of Inorganic Chemistry University of Duisburg-Essen Universitätsstraße 5–7 45141 Essen Germany
| | - Pratima Dhawan
- Institute of Inorganic Chemistry University of Duisburg-Essen Universitätsstraße 5–7 45141 Essen Germany
| | - Christoph Helling
- Institute of Inorganic Chemistry University of Duisburg-Essen Universitätsstraße 5–7 45141 Essen Germany
| | - Christoph Wölper
- Institute of Inorganic Chemistry University of Duisburg-Essen Universitätsstraße 5–7 45141 Essen Germany
| | - Stephan Schulz
- Institute of Inorganic Chemistry University of Duisburg-Essen Universitätsstraße 5–7 45141 Essen Germany
- Center for Nanointegration Duisburg-Essen (CENIDE) University of Duisburg-Essen Carl-Benz-Straße 199 47057 Duisburg Germany
| |
Collapse
|
27
|
Fuchs S, Jayaraman A, Krummenacher I, Haley L, Baštovanović M, Fest M, Radacki K, Helten H, Braunschweig H. Diboramacrocycles: reversible borole dimerisation-dissociation systems. Chem Sci 2022; 13:2932-2938. [PMID: 35382462 PMCID: PMC8905844 DOI: 10.1039/d1sc06908j] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 01/16/2022] [Indexed: 12/05/2022] Open
Abstract
We report that the outcome of the tin–boron exchange reaction of a mixed thiophene-benzo-fused stannole with aryldibromoboranes is associated with the steric bulk of the aryl substituent of the borane reagent, leading to either boroles or large diboracycles as products. NMR spectroscopic studies indicate that the two products can reversibly interconvert in solution, and mechanistic density functional theory (DFT) calculations reveal boroles to be intermediates in the formation of the diboracyclic products. The addition of Lewis bases to the diboracycles leads to the corresponding borole adducts, demonstrating that they react as “masked” boroles. Additionally, the reaction of the title compounds with a series of organic azides affords complex heteropropellanes, formally 2 : 1 borole-azide adducts, that deviate from the usual BN aromatic compounds formed via nitrogen atom insertion into the boroles. Diboramacrocycles are a new form of borole dimers, participating in various addition reactions as “masked” boroles. The reaction of a less crowded diboramacrocycle with organic azides affords unprecedented complex heteropropellanes.![]()
Collapse
Affiliation(s)
- Sonja Fuchs
- 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
| | - Arumugam Jayaraman
- 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
| | - 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
| | - Laura Haley
- 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
| | - Marta Baštovanović
- 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
| | - Maximilian Fest
- 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
| | - Krzysztof Radacki
- 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 Helten
- 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
|
28
|
Basappa S, Bhawar R, Nagaraju DH, Bose SK. Recent advances in the chemistry of the phosphaethynolate and arsaethynolate anions. Dalton Trans 2022; 51:3778-3806. [PMID: 35108724 DOI: 10.1039/d1dt03994f] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Over the past decade, the reactivity of 2-phosphaethynolate (OCP-), a heavier analogue of the cyanate anion, has been the subject of momentous interest in the field of modern organometallic chemistry. It is used as a precursor to novel phosphorus-containing heterocycles and as a ligand in decarbonylative processes, serving as a synthetic equivalent of a phosphinidene derivative. This perspective aims to describe advances in the reactivities of phosphaethynolate and arsaethynolate anions (OCE-; E = P, As) with main-group element, transition metal, and f-block metal scaffolds. Further, the unique structures and bonding properties are discussed based on spectroscopic and theoretical studies.
Collapse
Affiliation(s)
- Suma Basappa
- Centre for Nano and Material Sciences (CNMS), Jain University, Jain Global Campus, Bangalore-562112, India.
| | - Ramesh Bhawar
- Centre for Nano and Material Sciences (CNMS), Jain University, Jain Global Campus, Bangalore-562112, India.
| | - D H Nagaraju
- Department of Chemistry, School of Applied Sciences, Reva University, Bangalore 560064, India.
| | - Shubhankar Kumar Bose
- Centre for Nano and Material Sciences (CNMS), Jain University, Jain Global Campus, Bangalore-562112, India.
| |
Collapse
|
29
|
Dankert F, Hering-Junghans C. Heavier group 13/15 multiple bond systems: synthesis, structure and chemical bond activation. Chem Commun (Camb) 2022; 58:1242-1262. [PMID: 35014640 DOI: 10.1039/d1cc06518a] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Heavier group 13/15 multiple bonds have been under investigation since the late 80s and to date, several examples have been published, which shows the obsoleteness of the so-called double bond rule. Especially in the last few years, more and more group 13/15 multiple bonds became synthetically feasible and their application in terms of small molecule activation has been demonstrated. Our group has recently shown that the combination of the pnictinidene precursor DipTer-Pn(PMe3) (Pn = P, As) in combination with Al(I) synthons afforded the first examples of phospha- and arsaalumenes as isolable and thermally robust compounds. This feature article is intended to show the recent developments in the field, to outline early synthetic approaches and to discuss strategies to unlock the synthetic potential of these elusive chemical bonds.
Collapse
Affiliation(s)
- F Dankert
- Leibniz Institut für Katalyse e.V. (LIKAT), Albert-Einstein-Str. 29A, 18059 Rostock, Germany.
| | - C Hering-Junghans
- Leibniz Institut für Katalyse e.V. (LIKAT), Albert-Einstein-Str. 29A, 18059 Rostock, Germany.
| |
Collapse
|
30
|
Roesky HW, Kushvaha SK, Mishra A, Mondal KC. Recent advances in the domain of Cyclic (alkyl)(amino) carbenes. Chem Asian J 2022; 17:e202101301. [PMID: 34989475 PMCID: PMC9307053 DOI: 10.1002/asia.202101301] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/25/2021] [Indexed: 12/03/2022]
Abstract
Isolation of cyclic (alkyl) amino carbenes (cAACs) in 2005 has been a major achievement in the field of stable carbenes due to their better electronic properties. cAACs and bicyclic(alkyl)(amino)carbene (BicAAC) in essence are the most electrophilic as well as nucleophilic carbenes are known till date. Due to their excellent electronic properties in terms of nucleophilic and electrophilic character, cAACs have been utilized in different areas of chemistry, including stabilization of low valent main group and transition metal species, activation of small molecules, and catalysis. The applications of cAACs in catalysis have opened up new avenues of research in the field of cAAC chemistry. This review summarizes the major results of cAAC chemistry published until August 2021.
Collapse
Affiliation(s)
- Herbert W Roesky
- Georg-August-Universitat Gottingen, Department of Chemistry, Tammannstrasse 4, 37077, Göttingen, GERMANY
| | | | - Ankush Mishra
- IIT Madras: Indian Institute of Technology Madras, Chemistry, INDIA
| | | |
Collapse
|
31
|
Schoening J, Ganesamoorthy C, Wölper C, Solel E, Schreiner PR, Schulz S. Synthesis, electronic nature, and reactivity of selected silylene carbonyl complexes. Dalton Trans 2022; 51:8249-8257. [DOI: 10.1039/d2dt01335e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Room-temperature stable main group element carbonyl complexes are rare. Here we report on the synthesis of two such complexes, namely gallium-substituted silylene-carbonyl complexes [L(X)Ga]2SiCO (X = I 2, Me 3;...
Collapse
|
32
|
Obi AD, Machost HR, Dickie DA, Gilliard RJ. A Thermally Stable Magnesium Phosphaethynolate Grignard Complex. Inorg Chem 2021; 60:12481-12488. [PMID: 34346670 DOI: 10.1021/acs.inorgchem.1c01700] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The 2-phosphaethynolate (OCP) anion has found versatile applications across the periodic table but remains underexplored in group 2 chemistry due to challenges in isolating thermally stable complexes. By rationally modifying their coordination environments using 1,3-dialkyl-substituted N-heterocyclic carbenes (NHCs), we have now isolated and characterized thermally stable, structurally diverse, and hydrocarbon soluble magnesium phosphaethynolate complexes (2, 4Me, and 8-10), including the novel phosphaethynolate Grignard reagent (2iPr). The methylmagnesium phosphaethynolate and magnesium diphosphaethynolate complexes readily activate dioxane with subsequent H-atom abstraction to form [(NHC)MgX(μ-OEt)]2 [X = Me (3) or OCP (8 and 9)] complexes. Their reactivities increased with the Lewis acidity of the Mg2+ cation and may be attenuated by Lewis base saturation or a slight increase in carbene sterics. Solvent effects were also investigated and led to the surreptitious isolation of an ether-free sodium phosphaethynolate (NHC)3Na(OCP) (6), which is soluble in aromatic hydrocarbons and can be independently prepared by the reaction of NHC and [Na(dioxane)2][OCP] in toluene. Under forcing conditions (105 °C, 3 days), the magnesium diphosphaethynolate complex (NHC)3Mg(OCP)2 (10) decomposes to a mixture of organophosphorus complexes, among which a thermal decarbonylation product [(NHC)2PI][OCP] (11) was isolated.
Collapse
Affiliation(s)
- Akachukwu D Obi
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22904, United States
| | - Haleigh R Machost
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22904, United States
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22904, United States
| | - Robert J Gilliard
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22904, United States
| |
Collapse
|
33
|
Ota K, Kinjo R. Heavier element-containing aromatics of [4 n+2]-electron systems. Chem Soc Rev 2021; 50:10594-10673. [PMID: 34369490 DOI: 10.1039/d0cs01354d] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
While the implication of the aromaticity concept has been dramatically expanded to date since its emergence in 1865, the classical [4n+2]/4n-electron counting protocol still plays an essential role in evaluating the aromatic nature of compounds. Over the last few decades, a variety of heavier heterocycles featuring the formal [4n+2] π-electron arrangements have been developed, which allows for assessing their aromatic nature. In this review, we present recent developments of the [4n+2]-electron systems of heavier heterocycles involving group 13-15 elements. The synthesis, spectroscopic data, structural parameters, computational data, and reactivity are introduced.
Collapse
Affiliation(s)
- Kei Ota
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Nanyang Link 21, Singapore 637371, Singapore
| | - Rei Kinjo
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Nanyang Link 21, Singapore 637371, Singapore
| |
Collapse
|
34
|
Hagspiel S, Fantuzzi F, Dewhurst RD, Gärtner A, Lindl F, Lamprecht A, Braunschweig H. Adducts of the Parent Boraphosphaketene H 2 BPCO and their Decarbonylative Insertion Chemistry. Angew Chem Int Ed Engl 2021; 60:13666-13670. [PMID: 33843132 PMCID: PMC8252595 DOI: 10.1002/anie.202103521] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/08/2021] [Indexed: 01/06/2023]
Abstract
The first examples of Lewis base adducts of the parent boraphosphaketene (H2 B-PCO) and their cyclodimers are prepared. One of these adducts is shown to undergo mild decarbonylation and phosphinidene insertion into a B-C bond of a borole, forming very rare examples of 1,2-phosphaborinines, B/P isosteres of benzene. The strong donor properties of these 1,2-phosphaborinines are confirmed by the synthesis of their π complexes with the Group 6 metals.
Collapse
Affiliation(s)
- Stephan Hagspiel
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Felipe Fantuzzi
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Physical and Theoretical ChemistryJulius-Maximilians-Universität WürzburgEmil-Fischer-Strasse 4297074WürzburgGermany
| | - Rian D. Dewhurst
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Annalena Gärtner
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Felix Lindl
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Anna Lamprecht
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Holger Braunschweig
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| |
Collapse
|
35
|
Hagspiel S, Fantuzzi F, Dewhurst RD, Gärtner A, Lindl F, Lamprecht A, Braunschweig H. Addukte des Stammboraphosphaketens H
2
BPCO und deren Insertionsreaktionen mittels Decarbonylierung. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103521] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Stephan Hagspiel
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Felipe Fantuzzi
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für Physikalische und Theoretische Chemie Julius-Maximilians-Universität Würzburg Emil-Fischer-Straße 42 97074 Würzburg Deutschland
| | - Rian D. Dewhurst
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Annalena Gärtner
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Felix Lindl
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Anna Lamprecht
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Holger Braunschweig
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| |
Collapse
|
36
|
Wentz KE, Molino A, Weisflog SL, Kaur A, Dickie DA, Wilson DJD, Gilliard RJ. Stabilization of the Elusive 9-Carbene-9-Borafluorene Monoanion. Angew Chem Int Ed Engl 2021; 60:13065-13072. [PMID: 33780572 DOI: 10.1002/anie.202103628] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Indexed: 01/09/2023]
Abstract
Two-electron reduction of carbene-supported 9-bromo-9-borafluorenes with excess KC8 , Na, or Li-naphthalenide affords six N-heterocyclic carbene (NHC)- or cyclic(alkyl)(amino) carbene (CAAC)-stabilized borafluorene anions (3-8)-the first isolated and structurally authenticated examples of the elusive 9-carbene-9-borafluorene monoanion. The electronic structure, bonding, and aromaticity of the boracyclic anions were comprehensively investigated via computational studies. Compounds 5 and 8 react with metal halides via salt elimination to give new B-E (E=Au, Se, Ge)-containing materials (9-12). Upon reaction with diketones, the carbene ligand cleanly dissociates from 5 or 8 to yield new B-O containing spirocycles (13-14) that cannot be easily obtained using "normal" valent borafluorene compounds. Collectively, these results support the notion that carbene-stabilized monoanionic borafluorenes may serve as a new platform for the one-step construction of higher-value boracyclic materials.
Collapse
Affiliation(s)
- Kelsie E Wentz
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
| | - Andrew Molino
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, Latrobe University, Melbourne, 3086, Victoria, Australia
| | - Sarah L Weisflog
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
| | - Aishvaryadeep Kaur
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, Latrobe University, Melbourne, 3086, Victoria, Australia
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
| | - David J D Wilson
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, Latrobe University, Melbourne, 3086, Victoria, Australia
| | - Robert J Gilliard
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
| |
Collapse
|
37
|
Wentz KE, Molino A, Weisflog SL, Kaur A, Dickie DA, Wilson DJD, Gilliard RJ. Stabilization of the Elusive 9‐Carbene‐9‐Borafluorene Monoanion. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103628] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Kelsie E. Wentz
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| | - Andrew Molino
- Department of Chemistry and Physics La Trobe Institute for Molecular Science Latrobe University Melbourne 3086 Victoria Australia
| | - Sarah L. Weisflog
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| | - Aishvaryadeep Kaur
- Department of Chemistry and Physics La Trobe Institute for Molecular Science Latrobe University Melbourne 3086 Victoria Australia
| | - Diane A. Dickie
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| | - David J. D. Wilson
- Department of Chemistry and Physics La Trobe Institute for Molecular Science Latrobe University Melbourne 3086 Victoria Australia
| | - Robert J. Gilliard
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| |
Collapse
|
38
|
Chen X, Meng G, Liao G, Rauch F, He J, Friedrich A, Marder TB, Wang N, Chen P, Wang S, Yin X. Highly Emissive 9-Borafluorene Derivatives: Synthesis, Photophysical Properties and Device Fabrication. Chemistry 2021; 27:6274-6282. [PMID: 33496983 PMCID: PMC8048904 DOI: 10.1002/chem.202005185] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Indexed: 12/15/2022]
Abstract
A series of 9-borafluorene derivatives, functionalised with electron-donating groups, have been prepared. Some of these 9-borafluorene compounds exhibit strong yellowish emission in solution and in the solid state with relatively high quantum yields (up to 73.6 % for FMesB-Cz as a neat film). The results suggest that the highly twisted donor groups suppress charge transfer, but the intrinsic photophysical properties of the 9-borafluorene systems remain. The new compounds showed enhanced stability towards the atmosphere, and exhibited excellent thermal stability, revealing their potential for application in materials science. Organic light-emitting diode (OLED) devices were fabricated with two of the highly emissive compounds, and they exhibited strong yellow-greenish electroluminescence, with a maximum luminance intensity of >22 000 cd m-2 . These are the first two examples of 9-borafluorene derivatives being used as light-emitting materials in OLED devices, and they have enabled us to achieve a balance between maintaining their intrinsic properties while improving their stability.
Collapse
Affiliation(s)
- Xing Chen
- Key Laboratory of Cluster ScienceMinistry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of Technology102488BeijingP.R. China
| | - Guoyun Meng
- Key Laboratory of Cluster ScienceMinistry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of Technology102488BeijingP.R. China
| | - Guanming Liao
- Key Laboratory of Cluster ScienceMinistry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of Technology102488BeijingP.R. China
| | - Florian Rauch
- Institut für Anorganische ChemieInstitute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Jiang He
- Institut für Anorganische ChemieInstitute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Alexandra Friedrich
- Institut für Anorganische ChemieInstitute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Todd B. Marder
- Institut für Anorganische ChemieInstitute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Nan Wang
- Key Laboratory of Cluster ScienceMinistry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of Technology102488BeijingP.R. China
| | - Pangkuan Chen
- Key Laboratory of Cluster ScienceMinistry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of Technology102488BeijingP.R. China
| | - Suning Wang
- Key Laboratory of Cluster ScienceMinistry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of Technology102488BeijingP.R. China
- Department of ChemistryQueen's UniversityKingstonONK7L3N6Canada
| | - Xiaodong Yin
- Key Laboratory of Cluster ScienceMinistry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic, Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of Technology102488BeijingP.R. China
| |
Collapse
|
39
|
Walley JE, Warring LS, Kertész E, Wang G, Dickie DA, Benkő Z, Gilliard RJ. Indirect Access to Carbene Adducts of Bismuth- and Antimony-Substituted Phosphaketene and Their Unusual Thermal Transformation to Dipnictines and [(NHC) 2OCP][OCP]. Inorg Chem 2021; 60:4733-4743. [PMID: 33689349 PMCID: PMC8277130 DOI: 10.1021/acs.inorgchem.0c03683] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
![]()
The
synthesis and thermal redox chemistry of the first antimony
(Sb)– and bismuth (Bi)–phosphaketene adducts are described.
When diphenylpnictogen chloride [Ph2PnCl (Pn = Sb or Bi)]
is reacted with sodium 2-phosphaethynolate [Na[OCP]·(dioxane)x], tetraphenyldipnictogen (Ph2Pn–PnPh2) compounds are produced, and an insoluble
precipitate forms from solution. In contrast, when the N-heterocyclic carbene adduct (NHC)–PnPh2Cl is combined
with [Na[OCP]·(dioxane)x], Sb–
and Bi–phosphaketene complexes are isolated. Thus, NHC serves
as an essential mediator for the reaction. Immediately after the formation
of an intermediary pnictogen–phosphaketene NHC adduct [NHC–PnPh2(PCO)], the NHC ligand transfers from the Pn center to the
phosphaketene carbon atom, forming NHC–C(O)P-PnPh2 [Pn = Sb (3) or Bi (4)]. In the solid
state, 3 and 4 are dimeric with short intermolecular
Pn–Pn interactions. When compounds 3 and 4 are heated in THF at 90 and 70 °C, respectively, the
pnictogen center PnIII is thermally reduced to PnII to form tetraphenyldipnictines (Ph2Pn–PnPh2) and an unusual bis-carbene-supported OCP
salt, [(NHC)2OCP][OCP] (5). The formation
of compound 5 and Ph2Pn–PnPh2 from 3 or 4 is unique in comparison to
the known thermal reactivity for group 14 carbene–phosphaketene
complexes, further highlighting the diverse reactivity of [OCP]− with main-group elements. All new compounds have been
fully characterized by single-crystal X-ray diffraction, multinuclear
NMR spectroscopy (1H, 13C, and 31P), infrared spectroscopy, and elemental analysis (1, 2, and 5). The electronic structure of 5 and the mechanism of formation were investigated using density
functional theory (DFT). An N-heterocyclic carbene (NHC) was used
to support the otherwise unstable Ph2Sb—P=C=O
and Ph2Bi—P=C=O moieties. Exploration
of the thermal chemistry of these NHC−phosphaketene adducts
reveals the formation of the salt [NHC2OCP][OCP]. This
present work demonstrates the thermal chemistry of the 2-phospaethynolate
anion with heavier pnictogens (Sb and Bi).
Collapse
Affiliation(s)
- Jacob E Walley
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22903, United States
| | - Levi S Warring
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22903, United States
| | - Erik Kertész
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Szent Gellért tér 4, H-1111 Budapest, Hungary
| | - Guocang Wang
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22903, United States
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22903, United States
| | - Zoltán Benkő
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Szent Gellért tér 4, H-1111 Budapest, Hungary
| | - Robert J Gilliard
- Department of Chemistry, University of Virginia, 409 McCormick Road, P.O. Box 400319, Charlottesville, Virginia 22903, United States
| |
Collapse
|
40
|
Sharma MK, Wölper C, Haberhauer G, Schulz S. Vielseitiges Gallaphosphen: Von einem Ga‐P‐Ga‐Heteroallylkation über CO
2
‐Speicherung hin zu C(sp
3
)‐H‐Bindungsaktivierung. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014381] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mahendra K. Sharma
- Institut für Anorganische Chemie und Center für Nanointegration Duisburg-Essen (CENIDE) Universität Duisburg-Essen Universitätsstraße 5–7 45141 Essen Deutschland
| | - Christoph Wölper
- Institut für Anorganische Chemie und Center für Nanointegration Duisburg-Essen (CENIDE) Universität Duisburg-Essen Universitätsstraße 5–7 45141 Essen Deutschland
| | - Gebhard Haberhauer
- Institut für Organische Chemie Universität Duisburg-Essen Universitätsstraße 5–7 45141 Essen Deutschland
| | - Stephan Schulz
- Institut für Anorganische Chemie und Center für Nanointegration Duisburg-Essen (CENIDE) Universität Duisburg-Essen Universitätsstraße 5–7 45141 Essen Deutschland
| |
Collapse
|
41
|
Sharma MK, Wölper C, Haberhauer G, Schulz S. Multi-Talented Gallaphosphene for Ga-P-Ga Heteroallyl Cation Generation, CO 2 Storage, and C(sp 3 )-H Bond Activation. Angew Chem Int Ed Engl 2021; 60:6784-6790. [PMID: 33368922 PMCID: PMC7986129 DOI: 10.1002/anie.202014381] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Indexed: 11/12/2022]
Abstract
Gallaphosphene L(Cl)GaPGaL (2; L=HC[C(Me)N(2,6-i-Pr2 C6 H3 )]2 ), which is synthesized by reaction of LGa(Cl)PCO (1) with LGa, reacts with [Na(OCP)(dioxane)2.5 ] to LGa(OCP)PGaL (3), whereas chloride abstraction with LiBArF 4 yields [LGaPGaL][BArF 4 ] (4; BArF 4 =B(C6 F5 )4 ). 4 represents a heteronuclear analog of the allyl cation according to quantum chemical calculations. Remarkably, 2 reversibly reacts with CO2 to yield L(Cl)Ga-P[μ-C(O)O]2 GaL (5), while reactions with acetophenone and acetone selectively give compounds 6 and 7 by C(sp3 )-H bond activation.
Collapse
Affiliation(s)
- Mahendra K. Sharma
- Institute of Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE)University of Duisburg-EssenUniversitätsstrasse 5–745141EssenGermany
| | - Christoph Wölper
- Institute of Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE)University of Duisburg-EssenUniversitätsstrasse 5–745141EssenGermany
| | - Gebhard Haberhauer
- Institute of Organic ChemistryUniversity of Duisburg-EssenUniversitätsstrasse 5–745141EssenGermany
| | - Stephan Schulz
- Institute of Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE)University of Duisburg-EssenUniversitätsstrasse 5–745141EssenGermany
| |
Collapse
|
42
|
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
|
43
|
Wilson DWN, Myers WK, Goicoechea JM. Synthesis and decarbonylation chemistry of gallium phosphaketenes. Dalton Trans 2020; 49:15249-15255. [PMID: 33084675 DOI: 10.1039/d0dt03174g] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of gallium phosphaketenyl complexes supported by a 1,2-bis(aryl-imino)acenaphthene ligand (Dipp-Bian) are reported. Photolysis of one such species induced decarbonylation to afford a gallium substituted diphosphene. Addition of Lewis bases, specifically trimethylphosphine and the gallium carbenoid Ga(Nacnac) (Nacnac = HC[C(Me)N-(C6H3)-2,6-iPr2]2), resulted in displacement of the phosphaketene carbonyl to yield base-stabilised phosphinidenes. In several of these transformations, the redox non-innocence of the Dipp-Bian ligand was found to give rise to radical intermediates and/or side-products.
Collapse
Affiliation(s)
- Daniel W N Wilson
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - William K Myers
- Department of Chemistry, University of Oxford, Centre for Advanced ESR, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK
| | - Jose M Goicoechea
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| |
Collapse
|
44
|
Krantz KE, Weisflog SL, Frey NC, Yang W, Dickie DA, Webster CE, Gilliard RJ. Planar, Stair‐Stepped, and Twisted: Modulating Structure and Photophysics in Pyrene‐ and Benzene‐Fused N‐Heterocyclic Boranes. Chemistry 2020; 26:10072-10082. [DOI: 10.1002/chem.202002118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Indexed: 01/23/2023]
Affiliation(s)
- Kelsie E. Krantz
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| | - Sarah L. Weisflog
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| | - Nathan C. Frey
- Department of Chemistry Mississippi State University, Box 9573 Mississippi State MS 39762 USA
| | - Wenlong Yang
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| | - Diane A. Dickie
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| | - Charles Edwin Webster
- Department of Chemistry Mississippi State University, Box 9573 Mississippi State MS 39762 USA
| | - Robert J. Gilliard
- Department of Chemistry University of Virginia 409 McCormick Rd./ PO Box 400319 Charlottesville VA 22904 USA
| |
Collapse
|