1
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Li R, Gong ZL, Zhu Q, Sun MJ, Che Y, Yao J, Zhong YW. A pre-organized monomer-reservoir strategy to prepare multidimensional phosphorescent organoplatinum nanocrystals and suprastructures. Sci China Chem 2021. [DOI: 10.1007/s11426-021-1129-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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2
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Mai Y, Balzen AK, Torres RK, Callahan MP, Colson AC. A Modular Strategy for Expanding Electron-Sink Capacity in Noncanonical Cluster Assemblies. Inorg Chem 2021; 60:17733-17743. [PMID: 34748324 PMCID: PMC8653162 DOI: 10.1021/acs.inorgchem.1c02373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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A modular synthetic
strategy is described whereby organometallic
complexes exhibiting considerable electron-sink capacity may be assembled
by using only a few simple molecular components. The Fe2(PPh2)2(CO)5 fragment was selected
as a common electroactive component and was assembled around aromatic
cores bearing one, two, or three isocyanide functional groups, with
the resultant complexes possessing electron-sink capacities of two,
four, and six electrons, respectively. The latter complex is noteworthy
in that its electron-sink capacity was found to rival that of large
multinuclear clusters (e.g., [Ni32C6(CO)36]6– and [Ni38Pt6(CO)48]6–), which are often considered as benchmarks
of electron-sink behavior. Moreover, the modular assembly bearing
three Fe2(PPh2)2(CO)5 fragments
was observed to undergo reduction to a hexaanionic state over a potential
window of about −1.4 to −2.1 V (vs Fc/Fc+), the relatively compressed range being attributed to potential
inversions operative during the addition of the second, fourth, and
sixth electrons. Such complexes may be designated noncanonical
clusters because they exhibit redox properties similar to
those of large multinuclear clusters yet lack the extensive network
of metal–metal bonds and the condensed metallic cores that
typify the latter. By use of a
modular synthetic strategy and relatively few
molecular components, organometallic complexes exhibiting considerable
electron-sink capacity have been characterized. Complexes bearing
one, two, or three Fe2(PPh2)2(CO)5 fragments bound to aromatic isocyanide cores were found to
possess electron-sink capacities of two, four, and six electrons,
respectively, the latter rivaling the electron-sink capacity of large
polynuclear cluster benchmarks.
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Affiliation(s)
- Yume Mai
- Department of Chemistry and Biochemistry, Boise State University, Boise, Idaho 83725, United States
| | - Alexandria K Balzen
- Department of Chemistry and Biochemistry, Boise State University, Boise, Idaho 83725, United States
| | - Rebecca K Torres
- Department of Chemistry and Biochemistry, Boise State University, Boise, Idaho 83725, United States
| | - Michael P Callahan
- Department of Chemistry and Biochemistry, Boise State University, Boise, Idaho 83725, United States
| | - Adam C Colson
- Department of Chemistry and Biochemistry, Boise State University, Boise, Idaho 83725, United States
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3
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Im EJ, Jung HW, Kang YK. Evaluation of
Through‐Space
Electronic Coupling in the Cofacially Aligned
π‐Stacked
Organic
Mixed‐Valence
System. B KOREAN CHEM SOC 2021. [DOI: 10.1002/bkcs.12242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Eun Ji Im
- Department of Chemistry Sangmyung University Seoul 03016 South Korea
| | - Hae Won Jung
- Department of Chemistry Sangmyung University Seoul 03016 South Korea
| | - Youn K. Kang
- Department of Chemistry Sangmyung University Seoul 03016 South Korea
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4
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Tahara K, Abe M. Stimuli-responsive Mixed-valence Architectures: Synthetic Design and Interplay between Mobile and Introduced Charges. CHEM LETT 2020. [DOI: 10.1246/cl.200069] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Keishiro Tahara
- Department of Material Science, Graduate School of Material Science, University of Hyogo, 3-2-1 Kouto, Kamigori, Ako, Hyogo 678-1297, Japan
| | - Masaaki Abe
- Department of Material Science, Graduate School of Material Science, University of Hyogo, 3-2-1 Kouto, Kamigori, Ako, Hyogo 678-1297, Japan
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5
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Ou Y, Wang A, Yuan A, Yin C, Hu F. Phenyl‐Bridged Ferrocene/Ruthenium Alkynyl Heterobimetallic Complexes: Syntheses, Characterization, and Electrochemical, Spectroscopic, and Computational Investigation. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Ya‐Ping Ou
- College of Chemistry and Material Science Hengyang Normal University Key Laboratory of Functional Metal‐Organic Compounds of Hunan Province Key Laboratory of Functional Organometallic Materials of Hunan Province College Hengyang Hunan 421008 P.R. China
| | - Aihui Wang
- College of Chemistry and Material Science Hengyang Normal University Key Laboratory of Functional Metal‐Organic Compounds of Hunan Province Key Laboratory of Functional Organometallic Materials of Hunan Province College Hengyang Hunan 421008 P.R. China
| | - Ande Yuan
- College of Chemistry and Material Science Hengyang Normal University Key Laboratory of Functional Metal‐Organic Compounds of Hunan Province Key Laboratory of Functional Organometallic Materials of Hunan Province College Hengyang Hunan 421008 P.R. China
| | - Chuang Yin
- College of Chemistry and Material Science Hengyang Normal University Key Laboratory of Functional Metal‐Organic Compounds of Hunan Province Key Laboratory of Functional Organometallic Materials of Hunan Province College Hengyang Hunan 421008 P.R. China
| | - Fang Hu
- Faculty of Materials Science and Chemical Engineering Ningbo University 315211 Ningbo China
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6
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Puhl S, Steenbock T, Herrmann C, Heck J. Controlling Through‐Space and Through‐Bond Exchange Pathways in Bis‐Cobaltocenes for Molecular Spintronics. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201911999] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Sarah Puhl
- Department of ChemistryUniversity of Hamburg Martin-Luther-King-Platz 6 20146 Hamburg Germany
| | - Torben Steenbock
- Department of ChemistryUniversity of Hamburg Martin-Luther-King-Platz 6 20146 Hamburg Germany
| | - Carmen Herrmann
- Department of ChemistryUniversity of Hamburg Martin-Luther-King-Platz 6 20146 Hamburg Germany
| | - Jürgen Heck
- Department of ChemistryUniversity of Hamburg Martin-Luther-King-Platz 6 20146 Hamburg Germany
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7
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Puhl S, Steenbock T, Herrmann C, Heck J. Controlling Through-Space and Through-Bond Exchange Pathways in Bis-Cobaltocenes for Molecular Spintronics. Angew Chem Int Ed Engl 2019; 59:2407-2413. [PMID: 31705778 PMCID: PMC7004085 DOI: 10.1002/anie.201911999] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/06/2019] [Indexed: 11/21/2022]
Abstract
Pinching molecules via chemical strain suggests intuitive consequences, such as compression at the pinched site and clothespin‐like opening of other parts of the structure. If this opening affects two spin centers, it should result in reduced communication between them. We show that for naphthalene‐bridged biscobaltocenes with competing through‐space and through‐bond pathways, the consequences of pinching are far less intuitive: despite the known dominance of through‐space interactions, the bridge plays a much larger role for exchange spin coupling than previously assumed. Based on a combination of chemical synthesis, structural, magnetic, and redox characterization, and a newly developed theoretical pathway analysis, we can suggest a comprehensive explanation for this non‐intuitive behavior. These results are of interest for molecular spintronics, as naphthalene‐linked cobaltocenes can form wires on surfaces for potential spin‐only information transfer.
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Affiliation(s)
- Sarah Puhl
- Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany
| | - Torben Steenbock
- Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany
| | - Carmen Herrmann
- Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany
| | - Jürgen Heck
- Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany
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8
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Tahara K, Nakakita T, Starikova AA, Ikeda T, Abe M, Kikuchi JI. Small anion-assisted electrochemical potential splitting in a new series of bistriarylamine derivatives: organic mixed valency across a urea bridge and zwitterionization. Beilstein J Org Chem 2019; 15:2277-2286. [PMID: 31598180 PMCID: PMC6774064 DOI: 10.3762/bjoc.15.220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 09/05/2019] [Indexed: 11/23/2022] Open
Abstract
We report the synthesis of a new bistriarylamine series having a urea bridge and investigate its mixed-valence (MV) states by electrochemical and spectroelectrochemical methods. We found that the supporting electrolytes had unusual effects on potential splitting during electrochemical behavior, in which a smaller counteranion thermodynamically stabilized a MV cation more substantially than did a bulky one. The effects contrary to those reported in conventional MV systems were explained by zwitterionization through hydrogen bonding between the urea bridge and the counteranions, increasing the electronic interactions between two triarylamino units. Furthermore, we clarified the intervalence charge transfer characteristics of the zwitterionic MV state.
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Affiliation(s)
- Keishiro Tahara
- Department of Material Science, Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Ako, Hyogo 678-1297, Japan.,Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma, Nara 630-0192, Japan
| | - Tetsufumi Nakakita
- Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma, Nara 630-0192, Japan
| | - Alyona A Starikova
- Institute of Physical and Organic Chemistry, Southern Federal University, pr. Stachki 194/2, Rostov on Don, 344090, Russian Federation
| | - Takashi Ikeda
- Department of Material Science, Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Ako, Hyogo 678-1297, Japan
| | - Masaaki Abe
- Department of Material Science, Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Ako, Hyogo 678-1297, Japan
| | - Jun-Ichi Kikuchi
- Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma, Nara 630-0192, Japan
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9
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Makhoul R, Gluyas JBG, Vincent KB, Sahnoune H, Halet JF, Low PJ, Hamon JR, Lapinte C. Redox Properties of Ferrocenyl Ene-diynyl-Bridged Cp*(dppe)M–C≡C–1,4-(C6H4) Complexes. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00740] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rim Makhoul
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
| | - Josef B. G. Gluyas
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Kevin B. Vincent
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Hiba Sahnoune
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
- Département de Chimie, Faculté des Sciences, Université M’Hamed Bougara, Boumerdès, Algeria
| | - Jean-François Halet
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
| | - Paul J. Low
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Jean-René Hamon
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
| | - Claude Lapinte
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, F-35000 Rennes, France
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10
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Mondal S, Schwederski B, Frey W, Fiedler J, Záliš S, Kaim W. At the Borderline between Metal–Metal Mixed Valency and a Radical Bridge Situation: Four Charge States of a Diruthenium Complex with a Redox-Active Bis(mer-tridentate) Ligand. Inorg Chem 2018. [DOI: 10.1021/acs.inorgchem.8b00173] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Sudipta Mondal
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - Brigitte Schwederski
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - Wolfgang Frey
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - Jan Fiedler
- The Czech Academy of Sciences, J. Heyrovský Institute of Physical Chemistry, Dolejškova 3, 18223 Prague, Czech Republic
| | - Stanislav Záliš
- The Czech Academy of Sciences, J. Heyrovský Institute of Physical Chemistry, Dolejškova 3, 18223 Prague, Czech Republic
| | - Wolfgang Kaim
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
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11
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Triarylamines with branched multi-pyridine groups: modulation of emission properties by structural variation, solvents, and tris(pentafluorophenyl)borane. Sci China Chem 2018. [DOI: 10.1007/s11426-017-9202-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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12
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Shao JY, Gong ZL, Zhong YW. Bridged cyclometalated diruthenium complexes for fundamental electron transfer studies and multi-stage redox switching. Dalton Trans 2018; 47:23-29. [PMID: 29230470 DOI: 10.1039/c7dt04168c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Four bridged cyclometalated diruthenium systems are highlighted in this Frontier article, including strongly-coupled diruthenium complexes with a short phen-1,4-diyl or a planar pyren-2,7-diyl bridge, redox asymmetric diruthenium complexes characterized by different terminal ligands on the two ends, diruthenium complexes with a urea bridge that allows modulating the degree of electronic coupling, and those with a redox-active amine bridge with varying electronic structures. These complexes posess redox couples with low potentials and intense intervalence charge transfer absorptions in the near-infrared region in the one-electron-oxidized mixed-valent state. They are appealing not only for providing a platform for fundamental electron transfer studies but also as molecular materials with multi-stage redox switching properties.
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Affiliation(s)
- Jiang-Yang Shao
- CAS Key Laboratory of Photochemistry, CAS Research/Education Centre for Excellencet in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhong-Liang Gong
- CAS Key Laboratory of Photochemistry, CAS Research/Education Centre for Excellencet in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Yu-Wu Zhong
- CAS Key Laboratory of Photochemistry, CAS Research/Education Centre for Excellencet in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China and University of Chinese Academy of Sciences, Beijing 100049, China.
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13
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Hanft A, Lichtenberg C. Aminotroponiminates: ligand-centred, reversible redox events under oxidative conditions in sodium and bismuth complexes. Dalton Trans 2018; 47:10578-10589. [DOI: 10.1039/c8dt01019f] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Redox-active bismuth complexes based on a new aminotroponiminate ligand with ferrocenyl substituents have been synthesised and characterised.
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Affiliation(s)
- Anna Hanft
- Department of Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- D-97074 Würzburg
- Germany
| | - Crispin Lichtenberg
- Department of Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- D-97074 Würzburg
- Germany
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14
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Pienkos JA, Webster AB, Piechota EJ, Agakidou AD, McMillen CD, Pritchett DY, Meyer GJ, Wagenknecht PS. Oxidatively stable ferrocenyl-π-bridge-titanocene D–π-A complexes: an electrochemical and spectroscopic investigation of the mixed-valent states. Dalton Trans 2018; 47:10953-10964. [DOI: 10.1039/c8dt01853g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Coordination of CuI into RCp2Ti(C2Fc)2 compounds results in well-separated FeIII/II couples and mixed-valent states with distinct spectroscopic signatures.
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Affiliation(s)
| | | | - Eric J. Piechota
- Department of Chemistry
- The University of North Carolina at Chapel Hill
- Chapel Hill
- USA
| | | | | | | | - Gerald J. Meyer
- Department of Chemistry
- The University of North Carolina at Chapel Hill
- Chapel Hill
- USA
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15
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Gong ZL, Deng LY, Zhong YW, Yao J. Anion-regulated electronic communication in a cyclometalated diruthenium complex with a urea bridge. Phys Chem Chem Phys 2017; 19:8902-8907. [PMID: 28294210 DOI: 10.1039/c6cp08019g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A combined study of electrochemical measurements, intervalence charge transfer analysis, and DFT calculations suggests that the degree of urea-mediated electronic coupling between two cyclometalated ruthenium sites is enhanced by the coordination of urea with Br- or Cl-via hydrogen bonding. In contrast, the redox waves of the diruthenium complex become highly irreversible in the presence of relatively strong basic anions such as H2PO4-, F-, or OAc-. This work demonstrates that the anion-urea interaction can be employed to regulate the electronic coupling and electron transfer between redox-active sites, suggesting the potential applications of the urea-functionalized diruthenium complex in anion sensing and stimuli-responsive molecular electronics.
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Affiliation(s)
- Zhong-Liang Gong
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Li-Ye Deng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Yu-Wu Zhong
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiannian Yao
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and University of Chinese Academy of Sciences, Beijing 100049, China
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16
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Zhong YW, Gong ZL, Shao JY, Yao J. Electronic coupling in cyclometalated ruthenium complexes. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.01.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Kang MT, Meng M, Tan YN, Cheng T, Liu CY. Tuning the Electronic Coupling and Electron Transfer in Mo2 Donor-Acceptor Systems by Variation of the Bridge Conformation. Chemistry 2016; 22:3115-26. [PMID: 26807909 DOI: 10.1002/chem.201504033] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Indexed: 11/12/2022]
Abstract
Assembling two quadruply bonded dimolybdenum units [Mo2 (DAniF)3 ](+) (DAniF=N,N'-di(p-anisyl)formamidinate) with 1,4-naphthalenedicarboxylate and its thiolated derivatives produced three complexes [{Mo2 (DAniF)3 }2 (μ-1,4-O2 CC10 H6 CO2 )], [{Mo2 (DAniF)3 }2 (μ-1,4-OSCC10 H6 COS)], and [{Mo2 (DAniF)3 }2 (μ-1,4-S2 CC10 H6 CS2 )]. In the X-ray structures, the naphthalene bridge deviates from the plane defined by the two Mo-Mo bond vectors with the torsion angle increasing as the chelating atoms of the bridging ligand vary from O to S. The mixed-valent species exhibit intervalence transition absorption bands with high energy and very low intensity. In comparison with the data for the phenylene analogues, the optically determined electronic coupling matrix elements (Hab =258-345 cm(-1) ) are lowered by a factor of two or more, and the electron-transfer rate constants (ket ≈10(11) s(-1) ) are reduced by about one order of magnitude. These results show that, when the electron-transporting ability of the bridge and electron-donating (electron-accepting) ability of the donor (acceptor) are both variable, the former plays a dominant role in controlling the intramolecular electron transfer. DFT calculations revealed that increasing the torsion angle enlarges the HOMO-LUMO energy gap by elevating the (bridging) ligand-based LUMO energy. Therefore, our experimental results and theoretical analyses verify the superexchange mechanism for electronic coupling and electron transfer.
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Affiliation(s)
- Mei Ting Kang
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, P.R. China
| | - Miao Meng
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, P.R. China
| | - Ying Ning Tan
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, P.R. China
| | - Tao Cheng
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, P.R. China
| | - Chun Y Liu
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, P.R. China.
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18
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Zhang J, Sun CF, Zhang MX, Hartl F, Yin J, Yu GA, Rao L, Liu SH. Asymmetric oxidation of vinyl- and ethynyl terthiophene ligands in triruthenium complexes. Dalton Trans 2016; 45:768-82. [DOI: 10.1039/c5dt04083c] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Newly synthesized open-triangle triruthenium vinyl and ethynyl terthiophene complexes exhibit stepwise laterally localized oxidation processes, as revealed by UV-vis-NIR and IR spectroelectrochemistry.
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Affiliation(s)
- Jing Zhang
- Key Laboratory of Pesticide and Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - Chao-Fang Sun
- Key Laboratory of Pesticide and Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - Ming-Xing Zhang
- Key Laboratory of Pesticide and Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - František Hartl
- Department of Chemistry
- University of Reading
- Reading RG6 6AD
- UK
| | - Jun Yin
- Key Laboratory of Pesticide and Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - Guang-Ao Yu
- Key Laboratory of Pesticide and Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - Li Rao
- Key Laboratory of Pesticide and Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - Sheng Hua Liu
- Key Laboratory of Pesticide and Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
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19
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Zhang HL, Zhu GY, Wang G, Meng M, Liu CY, Lei H. Electronic Coupling in [Mo2]-Bridge-[Mo2] Systems with Twisted Bridges. Inorg Chem 2015; 54:11314-22. [PMID: 26579936 DOI: 10.1021/acs.inorgchem.5b01923] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In order to evaluate the impact of bridge conformation on electronic coupling in donor-bridge-acceptor triad systems, two Mo2 dimers, [Mo2(DAniF)3]2[μ-1,4-{C(O)NH}2-Naph] (1, DAniF = N,N'-di(p-anisyl)formamidinate and Naph = naphthalenyl) and [Mo2(DAniF)3]2[μ-1,4-(CS2)2-2,5-Me2C6H2] (2), have been synthesized and structurally characterized. These two compounds feature a large dihedral angle (>60°) between the central aromatic ring and the plane defined by the Mo-Mo bond vectors, which is distinct from the previously reported phenylene bridged analogues [Mo2(DAniF)3]2[μ-1,4-{C(O)NH}2-ph] (I) and [Mo2(DAniF)3]2[μ-1,4-(CS2)2-C6H4] (II), respectively. Unusual optical behaviors are observed for the mixed-valence (MV) species (1(+) and 2(+)), generated by single-electron oxidation. While 2(+) exhibits a weak intervalence charge transfer (IVCT) absorption band in the near-IR region, the IVCT band is absent in the spectrum of 1(+), which is quite different from what observed for I(+) and II(+). Optical analyses, based on superexchange formalism and Hush model, indicate that, in terms of Robin-Day classification, mixed-valence species 1(+) belongs to the electronically uncoupled Class I and complex 2(+), with Hab = 220 cm(-1), is assigned to the weakly coupled Class II. Together with I(+) and II(+), the four MV complexes complete a transition from Class I to Class II-III borderline as a result of manipulating the geometric topology of the bridge. Given the structural and electronic features for the molecular systems, the impacts of electrostatic interaction (through-space) and electron resonance (through-bond) on electronic coupling are discussed.
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Affiliation(s)
- Hong Li Zhang
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Guang Yuan Zhu
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Gangyi Wang
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Miao Meng
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Chun Y Liu
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Hao Lei
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou 510632, China
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Urea-bridged diferrocene: structural, electrochemical, and spectroelectrochemical studies. Sci China Chem 2015. [DOI: 10.1007/s11426-015-5423-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Zhu Q, Zhang Y, Nie H, Zhao Z, Liu S, Wong KS, Tang BZ. Insight into the strong aggregation-induced emission of low-conjugated racemic C6-unsubstituted tetrahydropyrimidines through crystal-structure-property relationship of polymorphs. Chem Sci 2015; 6:4690-4697. [PMID: 29142708 PMCID: PMC5667501 DOI: 10.1039/c5sc01226k] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 05/26/2015] [Indexed: 01/12/2023] Open
Abstract
Racemic C6-unsubstituted tetrahydropyrimidines (THPs) are a series of fluorophores with a strong aggregation-induced emission (AIE) effect. However, they do not possess the structural features of conventional AIE compounds. In order to understand their AIE mechanism, here, the influences of the molecular packing mode and the conformation on the optical properties of THPs were investigated using seven crystalline polymorphs of three THPs (1-3). The racemic THPs 1-3 have low-conjugated and highly flexible molecular structures, and hence show practically no emission in different organic solvents. However, the fluorescence quantum yields of their polymorphs are up to 93%, and the maximum excitation (λex) and emission (λem) wavelengths of the polymorphs are long at 409 and 484 nm, respectively. Single-crystal structures and theoretical calculation of the HOMOs and LUMOs based on the molecular conformations of these polymorphs indicate that the polymorphs with the shortest λex and λem values possess a RS-packing mode (R- and S-enantiomers self-assemble as paired anti-parallel lines) and a more twisted conformation without through-space conjugation between the dicarboxylates, but the polymorphs with longer λex and λem values adopt a RR/SS-packing mode (R- and S-enantiomers self-assemble as unpaired zigzag lines) and a less twisted conformation with through-space conjugation between the dicarboxylates. The molecular conformations of 1-3 in all these polymorphs are stereo and more twisted than those in solution. Although 1-3 are poorly conjugated, the radiative rate constants (kr) of their polymorphs are as large as conventional fluorophores (0.41-1.03 × 108 s-1) because of improved electronic conjugation by both through-bond and through-space interactions. Based on the obtained results, it can be deduced that the strong AIE arises not only from the restriction of intramolecular motion but also from enhanced electronic coupling and radiatively-favored inter-crossed local excitation (LE) and intramolecular charge transfer (ICT) excitation states. The abnormal molecular structures, easily-controllable self-assembly of the R- and S-enantiomers, and the strong AIE effect make THPs very useful fluorophores for applications and theoretical research.
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Affiliation(s)
- Qiuhua Zhu
- School of Pharmaceutical Sciences , Southern Medical University , 1838 Guangzhou Avenue North , Guangzhou 510515 , China .
| | - Yilin Zhang
- Department of Physics , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong .
| | - Han Nie
- Guangdong Innovative Research Team , State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
| | - Zujin Zhao
- Guangdong Innovative Research Team , State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
| | - Shuwen Liu
- School of Pharmaceutical Sciences , Southern Medical University , 1838 Guangzhou Avenue North , Guangzhou 510515 , China .
| | - Kam Sing Wong
- Department of Physics , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong .
| | - Ben Zhong Tang
- Guangdong Innovative Research Team , State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
- Department of Chemistry , State Key Laboratory of Molecular Neuroscience , Institute of Molecular Functional Materials , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong , China .
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