1
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Wang T, Guo Z, English LE, Stephan DW, Jupp AR, Xu M. Synthesis and Reactivity of the [NCCCO] - Cyanoketenate Anion. Angew Chem Int Ed Engl 2024; 63:e202402728. [PMID: 38483891 DOI: 10.1002/anie.202402728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Indexed: 04/11/2024]
Abstract
Cyanoketene is a fundamental molecule that is actively being searched for in the interstellar medium. Its deprotonated form (cyanoketenate) is a heterocumulene that is isoelectronic to carbon suboxide whose structure has been the subject of debate. However, the investigation of cyanoketene and its derivatives is hampered by the lack of practical synthetic routes to these compounds. We report the first synthesis of the cyanoketenate anion in [K(18-crown-6)][NCCCO] (1) as a stable molecule on a multigram scale in excellent yields (>90 %). The structure of this molecule is probed crystallographically and computationally. We also explore the protonation of 1, and its reaction with triphenylsilylchloride and carbon dioxide. In all cases, anionic dimers are formed. The cyanoketene could be synthesized and crystallographically characterized when stabilized by a N-heterocyclic carbene. The cyanoketenate is a very useful unsaturated building block containing N, C and O atoms that can now be explored with relative ease and will undoubtedly unlock more interesting reactivity.
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Affiliation(s)
- Tongtong Wang
- School of Chemical Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai, China, 200092
| | - Zhuangzhuang Guo
- School of Chemical Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai, China, 200092
| | - Laura E English
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham, West Midlands, UK, B15 2TT
| | - Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, Canada, M5S3H6
| | - Andrew R Jupp
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham, West Midlands, UK, B15 2TT
| | - Maotong Xu
- School of Chemical Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai, China, 200092
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2
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Pecorario S, Scaccabarozzi AD, Fazzi D, Gutiérrez-Fernández E, Vurro V, Maserati L, Jiang M, Losi T, Sun B, Tykwinski RR, Casari CS, Caironi M. Stable and Solution-Processable Cumulenic sp-Carbon Wires: A New Paradigm for Organic Electronics. Adv Mater 2022; 34:e2110468. [PMID: 35178779 DOI: 10.1002/adma.202110468] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Solution-processed, large-area, and flexible electronics largely relies on the excellent electronic properties of sp2 -hybridized carbon molecules, either in the form of π-conjugated small molecules and polymers or graphene and carbon nanotubes. Carbon with sp-hybridization, the foundation of the elusive allotrope carbyne, offers vast opportunities for functionalized molecules in the form of linear carbon atomic wires (CAWs), with intriguing and even superior predicted electronic properties. While CAWs represent a vibrant field of research, to date, they have only been applied sparingly to molecular devices. The recent observation of the field-effect in microcrystalline cumulenes suggests their potential applications in solution-processed thin-film transistors but concerns surrounding the stability and electronic performance have precluded developments in this direction. In the present study, ideal field-effect characteristics are demonstrated for solution-processed thin films of tetraphenyl[3]cumulene, the shortest semiconducting CAW. Films are deposited through a scalable, large-area, meniscus-coating technique, providing transistors with hole mobilities in excess of 0.1 cm2 V-1 s-1 , as well as promising operational stability under dark conditions. These results offer a solid foundation for the exploitation of a vast class of molecular semiconductors for organic electronics based on sp-hybridized carbon systems and create a previously unexplored paradigm.
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Affiliation(s)
- Stefano Pecorario
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
- Department of Energy, Micro and Nanostructured Materials Laboratory - NanoLab, Politecnico di Milano, Via Ponzio 34/3, Milano, 20133, Italy
| | - Alberto D Scaccabarozzi
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Daniele Fazzi
- Department of Chemistry "Giacomo Ciamician", Università di Bologna, Via F. Selmi, 2, Bologna, 40126, Italy
| | | | - Vito Vurro
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Lorenzo Maserati
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Mengting Jiang
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Tommaso Losi
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
| | - Bozheng Sun
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Rik R Tykwinski
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Carlo S Casari
- Department of Energy, Micro and Nanostructured Materials Laboratory - NanoLab, Politecnico di Milano, Via Ponzio 34/3, Milano, 20133, Italy
| | - Mario Caironi
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, via Giovanni Pascoli 70/3, Milano, 20133, Italy
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3
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Lenko I, Mamontov A, Alayrac C, Legay R, Witulski B. Media-Driven Pd-Catalyzed Reaction Cascades with 1,3-Diynamides Leading Selectively to Either Indoles or Quinolines. Angew Chem Int Ed Engl 2021; 60:22729-22734. [PMID: 34411395 DOI: 10.1002/anie.202110221] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Indexed: 11/10/2022]
Abstract
Divergent Pd-catalyzed reaction cascades with various 1,3-diynamides yielding either 2-amino-3-alkynylindoles or 2-amino-4-alkenylquinolines were established. Omitting or adding TBAF (tetrabutylammonium fluoride) to the reaction of N,N-(2-iodophenyl)(4-toluenesulfonyl)-1,3-diynamides with secondary or primary amines in the presence of KOH in THF and catalytic amounts of Pd(PPh3 )4 completely changed the outcome of the reaction. In the absence of TBAF, 2-amino-3-alkynylindoles were the sole products, while the presence of TBAF switched the product formation to 2-amino-4-alkenylquinolines. Deuterium labeling proceeded selectively at the C3 and C11 positions of the 2-amino-4-alkenylquinoline products and this suggests the unprecedented formation of [4]cumulenimines from 1,3-diynamides as reactive key intermediates.
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Affiliation(s)
- Illia Lenko
- Laboratoire de Chimie Moléculaire et Thio-organique, CNRS UMR 6507, ENSICAEN & UNICAEN, Normandie Univ., 6 Bvd Maréchal Juin, 14050, Caen, France
| | - Alexander Mamontov
- Laboratoire de Chimie Moléculaire et Thio-organique, CNRS UMR 6507, ENSICAEN & UNICAEN, Normandie Univ., 6 Bvd Maréchal Juin, 14050, Caen, France
| | - Carole Alayrac
- Laboratoire de Chimie Moléculaire et Thio-organique, CNRS UMR 6507, ENSICAEN & UNICAEN, Normandie Univ., 6 Bvd Maréchal Juin, 14050, Caen, France
| | - Rémi Legay
- Laboratoire de Chimie Moléculaire et Thio-organique, CNRS UMR 6507, ENSICAEN & UNICAEN, Normandie Univ., 6 Bvd Maréchal Juin, 14050, Caen, France
| | - Bernhard Witulski
- Laboratoire de Chimie Moléculaire et Thio-organique, CNRS UMR 6507, ENSICAEN & UNICAEN, Normandie Univ., 6 Bvd Maréchal Juin, 14050, Caen, France
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4
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Hirao Y, Daifuku Y, Ihara K, Kubo T. Spin-Spin Interactions in One-Dimensional Assemblies of a Cumulene-Based Singlet Biradical. Angew Chem Int Ed Engl 2021; 60:21319-21326. [PMID: 34101316 DOI: 10.1002/anie.202105740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Indexed: 11/09/2022]
Abstract
The synthesis of phenalenyl-endcapped [5]cumulene as a cumulene-based singlet biradical and the spin correlation changes of one-dimensional aggregates are described. The high propensity for self-aggregation of phenalenyl rings and the introduction of bulky substituents into the appropriate positions led to the formation of a one-dimensional chain assembly. Single-crystal X-ray structural analysis indicated that the bond length alternation of the cumulene chain increased with decreasing temperature, along with improved overlapping of the phenalenyl rings. Variable-temperature Raman spectroscopy and magnetic susceptibility measurements revealed that a localized spin pair within the molecule decouples at low temperatures, and a continuum spin system involving intra- and intermolecular spin-spin interactions emerges in the one-dimensional chain.
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Affiliation(s)
- Yasukazu Hirao
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Yoko Daifuku
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Keiji Ihara
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Takashi Kubo
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
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5
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Sánchez‐Grande A, Urgel JI, Cahlík A, Santos J, Edalatmanesh S, Rodríguez‐Sánchez E, Lauwaet K, Mutombo P, Nachtigallová D, Nieman R, Lischka H, de la Torre B, Miranda R, Gröning O, Martín N, Jelínek P, Écija D. Diradical Organic One-Dimensional Polymers Synthesized on a Metallic Surface. Angew Chem Int Ed Engl 2020; 59:17594-17599. [PMID: 32592432 PMCID: PMC7540677 DOI: 10.1002/anie.202006276] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/08/2020] [Indexed: 11/28/2022]
Abstract
We report on the synthesis and characterization of atomically precise one-dimensional diradical peripentacene polymers on a Au(111) surface. By means of high-resolution scanning probe microscopy complemented by theoretical simulations, we provide evidence of their magnetic properties, which arise from the presence of two unpaired spins at their termini. Additionally, we probe a transition of their magnetic properties related to the length of the polymer. Peripentacene dimers exhibit an antiferromagnetic (S=0) singlet ground state. They are characterized by singlet-triplet spin-flip inelastic excitations with an effective exchange coupling (Jeff ) of 2.5 meV, whereas trimers and longer peripentacene polymers reveal a paramagnetic nature and feature Kondo fingerprints at each terminus due to the unpaired spin. Our work provides access to the precise fabrication of polymers featuring diradical character which are potentially useful in carbon-based optoelectronics and spintronics.
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Affiliation(s)
| | - José I. Urgel
- IMDEA NanoscienceC/ Faraday 9, Campus de Cantoblanco28049MadridSpain
| | - Aleš Cahlík
- Institute of Physics of the Czech Academy of Science16253PrahaCzech Republic
- Regional Centre of Advanced Technologies and MaterialsPalacký University Olomouc77146OlomoucCzech Republic
| | - José Santos
- IMDEA NanoscienceC/ Faraday 9, Campus de Cantoblanco28049MadridSpain
- Departamento de Química OrgánicaFacultad de Ciencias QuímicasUniversidad Complutense de Madrid28040MadridSpain
| | - Shayan Edalatmanesh
- Institute of Physics of the Czech Academy of Science16253PrahaCzech Republic
- Regional Centre of Advanced Technologies and MaterialsPalacký University Olomouc77146OlomoucCzech Republic
| | | | - Koen Lauwaet
- IMDEA NanoscienceC/ Faraday 9, Campus de Cantoblanco28049MadridSpain
| | - Pingo Mutombo
- Institute of Physics of the Czech Academy of Science16253PrahaCzech Republic
| | - Dana Nachtigallová
- Regional Centre of Advanced Technologies and MaterialsPalacký University Olomouc77146OlomoucCzech Republic
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science16000PrahaCzech Republic
| | - Reed Nieman
- Department of Chemistry and BiochemistryTexas Tech UniversityLubbockTX79409USA
| | - Hans Lischka
- Department of Chemistry and BiochemistryTexas Tech UniversityLubbockTX79409USA
- School of Pharmaceutical Sciences and TechnologyTianjin UniversityTianjin300072P. R. China
| | - Bruno de la Torre
- Institute of Physics of the Czech Academy of Science16253PrahaCzech Republic
- Regional Centre of Advanced Technologies and MaterialsPalacký University Olomouc77146OlomoucCzech Republic
| | - Rodolfo Miranda
- IMDEA NanoscienceC/ Faraday 9, Campus de Cantoblanco28049MadridSpain
- Departamento de Física de la Materia CondensadaUniversidad Autónoma de Madrid28049MadridSpain
| | - Oliver Gröning
- EmpaSwiss Federal Laboratories for Materials Science and Technology8600DübendorfSwitzerland
| | - Nazario Martín
- IMDEA NanoscienceC/ Faraday 9, Campus de Cantoblanco28049MadridSpain
- Departamento de Química OrgánicaFacultad de Ciencias QuímicasUniversidad Complutense de Madrid28040MadridSpain
| | - Pavel Jelínek
- Institute of Physics of the Czech Academy of Science16253PrahaCzech Republic
- Regional Centre of Advanced Technologies and MaterialsPalacký University Olomouc77146OlomoucCzech Republic
| | - David Écija
- IMDEA NanoscienceC/ Faraday 9, Campus de Cantoblanco28049MadridSpain
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6
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Simserides C, Morphis A, Lambropoulos K. Hole Transfer in Open Carbynes. Materials (Basel) 2020; 13:E3979. [PMID: 32911864 PMCID: PMC7559821 DOI: 10.3390/ma13183979] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 08/31/2020] [Accepted: 09/04/2020] [Indexed: 01/29/2023]
Abstract
We investigate hole transfer in open carbynes, i.e., carbon atomic nanowires, using Real-Time Time-Dependent Density Functional Theory (RT-TDDFT). The nanowire is made of N carbon atoms. We use the functional B3LYP and the basis sets 3-21G, 6-31G*, cc-pVDZ, cc-pVTZ, cc-pVQZ. We also utilize a few Tight-Binding (TB) wire models, a very simple model with all sites equivalent and transfer integrals given by the Harrison ppπ expression (TBI) as well as a model with modified initial and final sites (TBImod) to take into account the presence of one or two or three hydrogen atoms at the edge sites. To achieve similar site occupations in cumulenes with those obtained by converged RT-TDDFT, TBImod is sufficient. However, to achieve similar frequency content of charge and dipole moment oscillations and similar coherent transfer rates, the TBImod transfer integrals have to be multiplied by a factor of four (TBImodt4times). An explanation for this is given. Full geometry optimization at the B3LYP/6-31G* level of theory shows that in cumulenes bond length alternation (BLA) is not strictly zero and is not constant, although it is symmetrical relative to the molecule center. BLA in cumulenic cases is much smaller than in polyynic cases, so, although not strictly, the separation to cumulenes and polyynes, approximately, holds. Vibrational analysis confirms that for N even all cumulenes with coplanar methylene end groups are stable, for N odd all cumulenes with perpendicular methylene end groups are stable, and the number of hydrogen atoms at the end groups is clearly seen in all cumulenic and polyynic cases. We calculate and discuss the Density Functional Theory (DFT) ground state energy of neutral molecules, the CDFT (Constrained DFT) "ground state energy" of molecules with a hole at one end group, energy spectra, density of states, energy gap, charge and dipole moment oscillations, mean over time probabilities to find the hole at each site, coherent transfer rates, and frequency content, in general. We also compare RT-TDDFT with TB results.
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Affiliation(s)
- Constantinos Simserides
- Department of Physics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, GR-15784 Athens, Greece; (A.M.); (K.L.)
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7
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Urgel JI, Di Giovannantonio M, Eimre K, Lohr TG, Liu J, Mishra S, Sun Q, Kinikar A, Widmer R, Stolz S, Bommert M, Berger R, Ruffieux P, Pignedoli CA, Müllen K, Feng X, Fasel R. On-Surface Synthesis of Cumulene-Containing Polymers via Two-Step Dehalogenative Homocoupling of Dibromomethylene-Functionalized Tribenzoazulene. Angew Chem Int Ed Engl 2020; 59:13281-13287. [PMID: 32350979 PMCID: PMC7496152 DOI: 10.1002/anie.202001939] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/29/2020] [Indexed: 11/24/2022]
Abstract
Cumulene compounds are notoriously difficult to prepare and study because their reactivity increases dramatically with the increasing number of consecutive double bonds. In this respect, the emerging field of on-surface synthesis provides exceptional opportunities because it relies on reactions on clean metal substrates under well-controlled ultrahigh-vacuum conditions. Here we report the on-surface synthesis of a polymer linked by cumulene-like bonds on a Au(111) surface via sequential thermally activated dehalogenative C-C coupling of a tribenzoazulene precursor equipped with two dibromomethylene groups. The structure and electronic properties of the resulting polymer with cumulene-like pentagon-pentagon and heptagon-heptagon connections have been investigated by means of scanning probe microscopy and spectroscopy methods and X-ray photoelectron spectroscopy, complemented by density functional theory calculations. Our results provide perspectives for the on-surface synthesis of cumulene-containing compounds, as well as protocols relevant to the stepwise fabrication of carbon-carbon bonds on surfaces.
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Affiliation(s)
- José I. Urgel
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Marco Di Giovannantonio
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Kristjan Eimre
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Thorsten G. Lohr
- Center for Advancing Electronics and Department of Chemistry and Food ChemistryTechnical University of Dresden01062DresdenGermany
| | - Junzhi Liu
- Center for Advancing Electronics and Department of Chemistry and Food ChemistryTechnical University of Dresden01062DresdenGermany
| | - Shantanu Mishra
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Qiang Sun
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Amogh Kinikar
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Roland Widmer
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Samuel Stolz
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
- Laboratory of Nanostructures at SurfacesInstitute of Physics, École Polytechnique Fédérale de LausanneCH-1015LausanneSwitzerland
| | - Max Bommert
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Reinhard Berger
- Center for Advancing Electronics and Department of Chemistry and Food ChemistryTechnical University of Dresden01062DresdenGermany
| | - Pascal Ruffieux
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Carlo A. Pignedoli
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
| | - Klaus Müllen
- Max Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
| | - Xinliang Feng
- Center for Advancing Electronics and Department of Chemistry and Food ChemistryTechnical University of Dresden01062DresdenGermany
| | - Roman Fasel
- Empa – Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland
- Department of Chemistry and BiochemistryUniversity of BernFreiestrasse 33012BernSwitzerland
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8
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Abstract
Allenes (carbodicarbenes) and [3]cumulenes are linear carbon chains that can be bent when the terminal group has a strong carbene nature. This bending can be quite pronounced in allenes but not in [3]cumulenes. In this study, how N-heterocyclic or cyclic (alkyl)(amino) carbene (NHC and CAAC, respectively) terminal groups can modify the linear structure of [n]cumulenes has been analyzed. A low π acidity of the terminal carbene affects the linearity of [2n]cumulenes. Indeed, it has been found that the NHC [4]cumulene is extremely bent, contrary to classical [4]cumulenes. The predicted NHC [4]cumulene or tricarbodicarbene has two lone pairs and the π electrons are delocalized over the whole molecule. More significantly, DFT calculations have shown that this bent [4]cumulene is very stable, considerably more so than the corresponding [3]cumulene, which has been elusive to synthesize. Remarkably, calculations have shown that all the NHC [2n]cumulenes are more than 25 kcal mol-1 more stable than the [2n-1]cumulenes.
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Affiliation(s)
- José Enrique Barquera-Lozada
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito exterior, Ciudad Universitaria Coyoacán, México, D.F., 04510, Mexico
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9
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Abstract
A mechanochemical synthesis of one-dimensional carbon allotrope carbyne model compounds, namely tetraaryl[n]cumulenes (n=3, 5) was realized. Central for the mechanosynthesis of the cumulenic carbon nanostructures were the development of a mechanochemical Favorskii alkynylation-type reaction and the implementation of a solvent-free, acid-free reductive elimination with tin(II) chloride by ball milling.
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Affiliation(s)
| | - Carsten Bolm
- Institute of Organic ChemistryRWTH Aachen UniversityLandoltweg 152074AachenGermany
| | - José G. Hernández
- Institute of Organic ChemistryRWTH Aachen UniversityLandoltweg 152074AachenGermany
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10
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Xu W, Leary E, Hou S, Sangtarash S, González MT, Rubio‐Bollinger G, Wu Q, Sadeghi H, Tejerina L, Christensen KE, Agraït N, Higgins SJ, Lambert CJ, Nichols RJ, Anderson HL. Unusual Length Dependence of the Conductance in Cumulene Molecular Wires. Angew Chem Int Ed Engl 2019; 58:8378-8382. [PMID: 31026371 PMCID: PMC6563095 DOI: 10.1002/anie.201901228] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/22/2019] [Indexed: 01/29/2023]
Abstract
Cumulenes are sometimes described as "metallic" because an infinitely long cumulene would have the band structure of a metal. Herein, we report the single-molecule conductance of a series of cumulenes and cumulene analogues, where the number of consecutive C=C bonds in the core is n=1, 2, 3, and 5. The [n]cumulenes with n=3 and 5 have almost the same conductance, and they are both more conductive than the alkene (n=1). This is remarkable because molecular conductance normally falls exponentially with length. The conductance of the allene (n=2) is much lower, because of its twisted geometry. Computational simulations predict a similar trend to the experimental results and indicate that the low conductance of the allene is a general feature of [n]cumulenes where n is even. The lack of length dependence in the conductance of [3] and [5]cumulenes is attributed to the strong decrease in the HOMO-LUMO gap with increasing length.
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Affiliation(s)
- Wenjun Xu
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryOxfordOX1 3TAUK
| | - Edmund Leary
- Department of ChemistryDonnan and Robert Robinson LaboratoriesUniversity of LiverpoolLiverpoolL69 7ZDUK
- Surface Science Research CentreUniversity of LiverpoolOxford StreetLiverpoolL69 3BXUK
| | - Songjun Hou
- Department of PhysicsLancaster UniversityLancasterLA1 4YWUK
| | | | - M. Teresa González
- Instituto Madrileño de Estudios Avanzados (IMDEA)Calle Faraday 9, Campus Universitario de Cantoblanco28049MadridSpain
| | - Gabino Rubio‐Bollinger
- Departamento de Física de la Materia CondensadaIFIMAC and Instituto “Nicolás Cabrera”Universidad Autónoma de Madrid28049MadridSpain
| | - Qingqing Wu
- Department of PhysicsLancaster UniversityLancasterLA1 4YWUK
| | - Hatef Sadeghi
- Department of PhysicsLancaster UniversityLancasterLA1 4YWUK
| | - Lara Tejerina
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryOxfordOX1 3TAUK
| | | | - Nicolás Agraït
- Instituto Madrileño de Estudios Avanzados (IMDEA)Calle Faraday 9, Campus Universitario de Cantoblanco28049MadridSpain
- Departamento de Física de la Materia CondensadaIFIMAC and Instituto “Nicolás Cabrera”Universidad Autónoma de Madrid28049MadridSpain
| | - Simon J. Higgins
- Department of ChemistryDonnan and Robert Robinson LaboratoriesUniversity of LiverpoolLiverpoolL69 7ZDUK
| | | | - Richard J. Nichols
- Department of ChemistryDonnan and Robert Robinson LaboratoriesUniversity of LiverpoolLiverpoolL69 7ZDUK
- Surface Science Research CentreUniversity of LiverpoolOxford StreetLiverpoolL69 3BXUK
| | - Harry L. Anderson
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryOxfordOX1 3TAUK
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11
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Spisak SN, Bühringer MU, Wei Z, Zhou Z, Tykwinski RR, Petrukhina MA. Structural and Electronic Effects of Stepwise Reduction of a Tetraaryl[3]Cumulene. Angew Chem Int Ed Engl 2019; 58:2023-2028. [PMID: 30560557 DOI: 10.1002/anie.201812283] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Indexed: 11/06/2022]
Abstract
The chemical reduction of a [3]cumulene ([3]TrTol) has been explored using alkali metals. Mono- and doubly reduced forms of [3]TrTol were isolated as solvent-separated ion pairs with {Na(18-crown-6)THF2 }+ and {K(18-crown-6)THF2 }+ counterions and crystallographically characterized. This allowed analysis of structural parameters of the "naked" anions of [3]TrTol without interference from metal binding. The dianion of [3]TrTol was also isolated as a contact-ion complex with {Cs(18-crown-6)}+ cations, thereby adding the effect of metal coordination to the core. Structural comparisons of anions to the neutral molecule, [3]TrTol, outline monotonic increases in bond-length alternation (BLA) upon stepwise reduction. The greatest BLA value is found for the contact-ion complex, which shows an alternating sequence of short and long carbon-carbon bonds, consistent with the structure of an alkyne. In contrast to studies on tetraphenyl[3]cumulene, the cumulenic framework of [3]TrTol remains planar in all the derivatives.
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Affiliation(s)
- Sarah N Spisak
- Department of Chemistry, University at Albany, State University of New York, Albany, NY, 12222, USA
| | - Martina U Bühringer
- Department für Chemie und Pharmazie & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Strasse 10, 91058, Erlangen, Germany
| | - Zheng Wei
- Department of Chemistry, University at Albany, State University of New York, Albany, NY, 12222, USA
| | - Zheng Zhou
- Department of Chemistry, University at Albany, State University of New York, Albany, NY, 12222, USA
| | - Rik R Tykwinski
- Department für Chemie und Pharmazie & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Strasse 10, 91058, Erlangen, Germany.,Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada
| | - Marina A Petrukhina
- Department of Chemistry, University at Albany, State University of New York, Albany, NY, 12222, USA
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Sun Q, Tran BV, Cai L, Ma H, Yu X, Yuan C, Stöhr M, Xu W. On-Surface Formation of Cumulene by Dehalogenative Homocoupling of Alkenyl gem-Dibromides. Angew Chem Int Ed Engl 2017; 56:12165-12169. [PMID: 28772061 DOI: 10.1002/anie.201706104] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Indexed: 11/09/2022]
Abstract
The on-surface activation of carbon-halogen groups is an efficient route to produce radicals for constructing various hydrocarbons and carbon nanostructures. To date, the employed halide precursors have only one halogen attached to a carbon atom. It is thus of interest to study the effect of attaching more than one halogen atom to a carbon atom with the aim of producing multiple unpaired electrons. By introducing an alkenyl gem-dibromide, cumulene products were fabricated on a Au(111) surface by dehalogenative homocoupling reactions. The reaction products and pathways were unambiguously characterized by a combination of high-resolution scanning tunneling microscopy and non-contact atomic force microscopy measurements together with density functional calculations. This study further supplements the database of on-surface synthesis strategies and provides a facile manner for incorporation of more complicated carbon scaffolds into surface nanostructures.
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Affiliation(s)
- Qiang Sun
- Interdisciplinary Materials Research Center, Tongji-Aarhus Joint Research Center for Nanostructures and Functional Nanomaterials, College of Materials Science and Engineering, Tongji University, Shanghai, 201804, P. R. China
| | - Bay V Tran
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747, AG, Groningen, The Netherlands
| | - Liangliang Cai
- Interdisciplinary Materials Research Center, Tongji-Aarhus Joint Research Center for Nanostructures and Functional Nanomaterials, College of Materials Science and Engineering, Tongji University, Shanghai, 201804, P. R. China
| | - Honghong Ma
- Interdisciplinary Materials Research Center, Tongji-Aarhus Joint Research Center for Nanostructures and Functional Nanomaterials, College of Materials Science and Engineering, Tongji University, Shanghai, 201804, P. R. China
| | - Xin Yu
- Interdisciplinary Materials Research Center, Tongji-Aarhus Joint Research Center for Nanostructures and Functional Nanomaterials, College of Materials Science and Engineering, Tongji University, Shanghai, 201804, P. R. China
| | - Chunxue Yuan
- Interdisciplinary Materials Research Center, Tongji-Aarhus Joint Research Center for Nanostructures and Functional Nanomaterials, College of Materials Science and Engineering, Tongji University, Shanghai, 201804, P. R. China
| | - Meike Stöhr
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747, AG, Groningen, The Netherlands
| | - Wei Xu
- Interdisciplinary Materials Research Center, Tongji-Aarhus Joint Research Center for Nanostructures and Functional Nanomaterials, College of Materials Science and Engineering, Tongji University, Shanghai, 201804, P. R. China
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Marshall JL, Lehnherr D, Lindner BD, Tykwinski RR. Reductive Aromatization/Dearomatization and Elimination Reactions to Access Conjugated Polycyclic Hydrocarbons, Heteroacenes, and Cumulenes. Chempluschem 2017; 82:967-1001. [PMID: 31961601 DOI: 10.1002/cplu.201700168] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/18/2017] [Indexed: 11/12/2022]
Abstract
Acenes, heteroacenes, conjugated polycyclic hydrocarbons, and polycyclic aromatic hydrocarbons (collectively referred to in this review as conjugated polycyclic molecules, CPMs) have fascinated chemists since they were first isolated and synthesized in the mid 19th century. Most recently, these compounds have shown significant promise as the active components in organic devices (e.g., solar cells, thin-film transistors, light-emitting diodes, etc.), and, since 2001, a plethora of publications detail synthetic strategies to produce CPMs. In this review, we discuss reductive aromatization, reductive dearomatization, and elimination/extrusion reactions used to form CPMs. After a brief discussion on early methods to synthesize CPMs, we detail the use of reagents used for the reductive (de)aromatization of precursors containing 1,4-diols/diethers, including SnCl2 and iodide (I- ). Extension of these methods to carbomers and cumulenes is briefly discussed. We then describe low-valent metal species used to reduce endoxides to CPMs, and discuss the methods to directly reduce acenediones and acenones to the respective acene. In the final section, we describe methods used to affect aromatization to the desired CPM via extrusion of small, volatile molecules.
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Affiliation(s)
- Jonathan L Marshall
- Department of Chemistry, Gunning-Lemieux Chemistry Center, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Dan Lehnherr
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Benjamin D Lindner
- Department for Chemistry and Pharmacy, and Interdisciplinary Center for Molecular Materials (ICCM), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Henkestrasse 42, 91054, Erlangen, Germany
| | - Rik R Tykwinski
- Department of Chemistry, Gunning-Lemieux Chemistry Center, University of Alberta, Edmonton, AB, T6G 2G2, Canada.,Department for Chemistry and Pharmacy, and Interdisciplinary Center for Molecular Materials (ICCM), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Henkestrasse 42, 91054, Erlangen, Germany
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Alcaide B, Almendros P, Cembellín S, Fernández I, Martínez Del Campo T. Metal-Catalyzed Cyclization Reactions of 2,3,4-Trien-1-ols: A Joint Experimental-Computational Study. Chemistry 2016; 22:11667-76. [PMID: 27383332 DOI: 10.1002/chem.201601838] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Indexed: 01/26/2023]
Abstract
Controlled preparation of tri- and tetrasubstituted furans, as well as carbazoles has been achieved through chemo- and regioselective metal-catalyzed cyclization reactions of cumulenic alcohols. The gold- and palladium-catalyzed cycloisomerization reactions of cumulenols, including indole-tethered 2,3,4-trien-1-ols, to trisubstituted furans was effective, due to a 5-endo-dig oxycyclization by attack of the hydroxy group onto the central cumulene double bond. In contrast, palladium-catalyzed heterocyclization/coupling reactions with 3-bromoprop-1-enes furnished tetrasubstituted furans. Also studied was the palladium-catalyzed cyclization/coupling sequence involving protected indole-tethered 2,3,4-trien-1-ols and 3-bromoprop-1-enes that exclusively generated trisubstituted carbazole derivatives. These results could be explained through a selective 6-endo-dig cumulenic hydroarylation, followed by aromatization. DFT calculations were carried out to understand this difference in reactivity.
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Affiliation(s)
- Benito Alcaide
- Grupo de Lactamas y Heterociclos Bioactivos, Departamento de Química Orgánica I, Unidad Asociada al CSIC, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain.
| | - Pedro Almendros
- Instituto de Qímica General, Consejo Superior de Investigaciones Científicas, IQOG-CSIC, Juan de la Cierva 3, 28006, Madrid, Spain.
| | - Sara Cembellín
- Grupo de Lactamas y Heterociclos Bioactivos, Departamento de Química Orgánica I, Unidad Asociada al CSIC, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain
| | - Israel Fernández
- Departamento de Química Orgánica I, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain.
| | - Teresa Martínez Del Campo
- Grupo de Lactamas y Heterociclos Bioactivos, Departamento de Química Orgánica I, Unidad Asociada al CSIC, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain
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Abstract
For the last 60+ years, the synthesis and study of cumulenes and polyynes have been the focus of a small, but dedicated, group of researchers. Many of the remarkable electronic, optical, and structural properties of cumulenes and polyynes had already been identified in the earliest reports. The molecular lengths achievable by the initial syntheses were, unfortunately, somewhat limited by synthetic methods available. For the past 15 years, we have worked toward expanding on the synthesis of cumulenes and polyynes through the development of new methods and stabilization motifs. As new compounds have become available, homologous series of cumulenes and polyynes have then been examined as a function of molecular length. While we are not yet there, we would like to eventually provide a general description of the sp-carbon allotrope carbyne, and this account presents some of our efforts toward this goal.
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Affiliation(s)
- Rik R Tykwinski
- Department of Chemistry and Pharmacy & Interdisciplinary Center of Molecular Materials (ICMM), University of Erlangen-Nuremberg, Henkestrasse 42, 91054, Erlangen, Germany.
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Milani A, Tommasini M, Russo V, Li Bassi A, Lucotti A, Cataldo F, Casari CS. Raman spectroscopy as a tool to investigate the structure and electronic properties of carbon-atom wires. Beilstein J Nanotechnol 2015; 6:480-91. [PMID: 25821689 PMCID: PMC4362090 DOI: 10.3762/bjnano.6.49] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 01/14/2015] [Indexed: 05/24/2023]
Abstract
Graphene, nanotubes and other carbon nanostructures have shown potential as candidates for advanced technological applications due to the different coordination of carbon atoms and to the possibility of π-conjugation. In this context, atomic-scale wires comprised of sp-hybridized carbon atoms represent ideal 1D systems to potentially downscale devices to the atomic level. Carbon-atom wires (CAWs) can be arranged in two possible structures: a sequence of double bonds (cumulenes), resulting in a 1D metal, or an alternating sequence of single-triple bonds (polyynes), expected to show semiconducting properties. The electronic and optical properties of CAWs can be finely tuned by controlling the wire length (i.e., the number of carbon atoms) and the type of termination (e.g., atom, molecular group or nanostructure). Although linear, sp-hybridized carbon systems are still considered elusive and unstable materials, a number of nanostructures consisting of sp-carbon wires have been produced and characterized to date. In this short review, we present the main CAW synthesis techniques and stabilization strategies and we discuss the current status of the understanding of their structural, electronic and vibrational properties with particular attention to how these properties are related to one another. We focus on the use of vibrational spectroscopy to provide information on the structural and electronic properties of the system (e.g., determination of wire length). Moreover, by employing Raman spectroscopy and surface enhanced Raman scattering in combination with the support of first principles calculations, we show that a detailed understanding of the charge transfer between CAWs and metal nanoparticles may open the possibility to tune the electronic structure from alternating to equalized bonds.
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Affiliation(s)
- Alberto Milani
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- NEMAS – Center for NanoEngineered Materials and Surfaces, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
| | - Matteo Tommasini
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- NEMAS – Center for NanoEngineered Materials and Surfaces, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
| | - Valeria Russo
- NEMAS – Center for NanoEngineered Materials and Surfaces, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
- Department of Energy, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
| | - Andrea Li Bassi
- NEMAS – Center for NanoEngineered Materials and Surfaces, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
- Department of Energy, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
| | - Andrea Lucotti
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- NEMAS – Center for NanoEngineered Materials and Surfaces, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
| | - Franco Cataldo
- Dipartimento di Scienze Ecologiche e Biologiche, Università della Tuscia, Via Camillo de Lellis, Viterbo, Italy
- Actinium Chemical Research srl, Via Casilina 1626A, 00133 Roma, Italy
| | - Carlo S Casari
- NEMAS – Center for NanoEngineered Materials and Surfaces, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
- Department of Energy, Politecnico di Milano, via Ponzio 34/3, 20133 Milano, Italy
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Bercovici DA, Ogilvie JM, Tsvetkov N, Brewer M. Intramolecular polar [4(⊕)+2] cycloadditions of aryl-1-aza-2-azoniaallene salts: unprecedented reactivity leading to polycyclic protonated azomethine imines. Angew Chem Int Ed Engl 2013; 52:13338-41. [PMID: 24218159 DOI: 10.1002/anie.201306553] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 09/24/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Daniel A Bercovici
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, VT 05405 (USA)
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Arkhypchuk AI, Orthaber A, Mihali VA, Ehlers A, Lammertsma K, Ott S. Oxaphospholes and bisphospholes from phosphinophosphonates and α,β-unsaturated ketones. Chemistry 2013; 19:13692-704. [PMID: 24038188 PMCID: PMC4304286 DOI: 10.1002/chem.201302014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Indexed: 12/04/2022]
Abstract
The reaction of a {W(CO)5 }-stabilized phosphinophosphonate 1, (CO)5 WPH(Ph)P(O)(OEt)2 , with ethynyl- (2 a-f) and diethynylketones (7-11, 18, and 19) in the presence of lithium diisopropylamide (LDA) is examined. Lithiated 1 undergoes nucleophilic attack in the Michael position of the acetylenic ketones, as long as this position is not sterically encumbered by bulky (iPr)3 Si substituents. Reaction of all other monoacetylenic ketones with lithiated 1 results in the formation of 2,5-dihydro-1,2-oxaphospholes 3 and 4. When diacetylenic ketones are employed in the reaction, two very different product types can be isolated. If at least one (Me)3 Si or (Et)3 Si acetylene terminus is present, as in 7, 8, and 19, an anionic oxaphosphole intermediate can react further with a second equivalent of ketone to give cumulene-decorated oxaphospholes 14, 15, 24, and 25. Diacetylenic ketones 10 and 11, with two aromatic acetylene substituents, react with lithitated 1 to form exclusively ethenyl-bridged bisphospholes 16 and 17. Mechanisms that rationalize the formation of all heterocycles are presented and are supported by DFT calculations. Computational studies suggest that thermodynamic, as well as kinetic, considerations dictate the observed reactivity. The calculated reaction pathways reveal a number of almost isoenergetic intermediates that follow after ring opening of the initially formed oxadiphosphetane. Bisphosphole formation through a carbene intermediate G is greatly favored in the presence of phenyl substituents, whereas the formation of cumulene-decorated oxaphospholes is more exothermic for the trimethylsilyl-containing substrates. The pathway to the latter compounds contains a 1,3-shift of the group that stems from the acetylene terminus of the ketone substrates. For silyl substituents, the 1,3-shift proceeds along a smooth potential energy surface through a transition state that is characterized by a pentacoordinated silicon center. In contrast, a high-lying transition state TS(E'-F')R=Ph of 37 kcal mol(-1) is found when the substituent is a phenyl group, thus explaining the experimental observation that aryl-terminated diethynylketones 10 and 11 exclusively form bisphospholes 16 and 17.
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Affiliation(s)
- Anna I Arkhypchuk
- Department of Chemistry, Ångström Laboratories, Uppsala University, Box 523, 751 20 Uppsala (Sweden)
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