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Ishtaiwi Z, Taher D, Korb M, Helal W, Al-Hunaiti A, Juwhari HK, Amarne H, Amer MW, YouSef YA, Klaib S, Abu-Orabi ST. Syntheses, crystal structures, DFT calculation and solid-state spectroscopic properties of new zincate(II) complexes with N-(4-substituted phenyl)-N'-(4-nitrophenyl)-oxamate. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2022.104349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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2
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Squire IAZ, Goult CA, Thompson BC, Alexopoulos E, Whitwood AC, Tanner TFN, Wilkinson LA. Enhancing the Air Stability of Dimolybdenum Paddlewheel Complexes: Redox Tuning through Fluorine Substituents. Inorg Chem 2022; 61:19144-19155. [DOI: 10.1021/acs.inorgchem.2c02746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
| | | | | | - Elias Alexopoulos
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - Adrian C. Whitwood
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - Theo F. N. Tanner
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - Luke A. Wilkinson
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
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3
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Mallick S, Zhou Y, Chen X, Tan YN, Meng M, Cao L, Qin Y, He ZC, Cheng T, Zhu GY, Liu CY. A Single Solvating Benzene Molecule Decouples the Mixed-valence Complex through Intermolecular Orbital Interactions. iScience 2022; 25:104365. [PMID: 35620431 PMCID: PMC9126792 DOI: 10.1016/j.isci.2022.104365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/10/2022] [Accepted: 05/02/2022] [Indexed: 11/19/2022] Open
Abstract
Characterization of covalency of intermolecular interactions in the van der Waals distance limit remains challenging because the interactions between molecules are weak, dynamic, and not measurable. Herein, we approach this issue in a series of supramolecular mixed-valence (MV) donor(D)-bridge(B)-acceptor(A) systems consisting of two bridged Mo2 units with a C6H6 molecule encapsulated, as characterized by the X-ray crystal structures. Comparative analysis of the intervalence charge transfer spectra in benzene and dichloromethane substantiates the strong electronic decoupling effect of the solvating C6H6 molecule that breaks down the dielectric solvation theory. Ab initio and DFT calculations unravel that the intermolecular orbital overlaps between the complex bridge and the C6H6 molecule alter the electronic states of the D-B-A molecule through intermolecular nuclear dynamics. This work exemplifies that site-specific intermolecular interaction can be exploited to control the chemical property of supramolecular systems and to elucidate the functionalities of side-chains in biological systems. Decoupling mixed-valence complexes by an encapsulated benzene molecule Demonstrating intermolecular orbital interactions in the van der Waals distances Illustrating interplay between intermolecular electronic and nuclear degrees of freedom
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Affiliation(s)
- Suman Mallick
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Yuli Zhou
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Xiaoli Chen
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Ying Ning Tan
- 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
- Corresponding author
| | - Lijiu Cao
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Yi Qin
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Zi Cong He
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Tao Cheng
- 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
| | - Chun Y. Liu
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China
- Corresponding author
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4
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Aust M, Herold AJ, Niederegger L, Schneider C, Mayer DC, Drees M, Warnan J, Pöthig A, Fischer RA. Introducing Benzene-1,3,5-tri(dithiocarboxylate) as a Multidentate Linker in Coordination Chemistry. Inorg Chem 2021; 60:19242-19252. [PMID: 34870417 DOI: 10.1021/acs.inorgchem.1c03045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Benzene-1,3,5-tri(dithiocarboxylate) (BTDTC3-), the sulfur-donor analogue of trimesate (BTC3-, benzene-1,3,5-tricarboxylate), is introduced, and its potential as a multidentate, electronically bridging ligand in coordination chemistry is evaluated. For this, the sodium salt Na3BTDTC has been synthesized, characterized, and compared with the sodium salt of the related ditopic benzene-1,4-di(dithiocarboxylate) (Na2BDDTC). Single-crystal X-ray diffraction of the respective tetrahydrofuran (THF) solvates reveals that such multitopic aromatic dithiocarboxylate linkers can form both discrete metal complexes (Na3BTDTC·9THF) and (two-dimensional) coordination polymers (Na2BDDTC·4THF). Additionally, the versatile coordination behavior of the novel BTDTC3- ligand is demonstrated by successful synthesis and characterization of trinuclear Cu(I) and hexanuclear Mo(II)2 paddlewheel complexes. The electronic structure and molecular orbitals of both dithiocarboxylate ligands as well as their carboxylate counterparts are investigated by density functional theory computational methods. Electrochemical investigations suggest that BTDTC3- enables electronic communication between the coordinated metal ions, rendering it a promising tritopic linker for functional coordination polymers.
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Affiliation(s)
- Margit Aust
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Anna J Herold
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Lukas Niederegger
- Assistant Professorship of Bioinorganic Chemistry, Catalysis Research Center, Technical University of Munich, Ernst-Otto-Fischer Straße 1, 85748 Garching, Germany
| | - Christian Schneider
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
| | - David C Mayer
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Markus Drees
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Julien Warnan
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Alexander Pöthig
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Roland A Fischer
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
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5
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Rodríguez-López N, Metta N, Metta-Magana AJ, Villagrán D. Redox Potential Tuning of Dimolybdenum Systems through Systematic Substitution by Guanidinate Ligands. Inorg Chem 2020; 59:3091-3101. [DOI: 10.1021/acs.inorgchem.9b03394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nancy Rodríguez-López
- Department of Chemistry and Biochemistry, The University of Texas at El Paso, El Paso, Texas 79968, United States
| | - Nathalie Metta
- Department of Chemistry and Biochemistry, The University of Texas at El Paso, El Paso, Texas 79968, United States
| | - Alejandro J. Metta-Magana
- Department of Chemistry and Biochemistry, The University of Texas at El Paso, El Paso, Texas 79968, United States
| | - Dino Villagrán
- Department of Chemistry and Biochemistry, The University of Texas at El Paso, El Paso, Texas 79968, United States
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6
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Cui HH, Lu F, Chen XT, Zhang YQ, Tong W, Xue ZL. Zero-Field Slow Magnetic Relaxation and Hysteresis Loop in Four-Coordinate Co II Single-Ion Magnets with Strong Easy-Axis Anisotropy. Inorg Chem 2019; 58:12555-12564. [PMID: 31553166 DOI: 10.1021/acs.inorgchem.9b01175] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Two mononuclear tetrahedral Co(II) complexes (HNEt3)2[Co(L1)2]·H2O (1) and (Bu4N)2[Co(L2)2]·H2O (2) (H2L1 = N,N'-bis(p-toluenesulfony1)oxamide, H2L2 = N,N'-diphenyloxamide) have been synthesized, and their structures have been characterized by single-crystal X-ray diffraction. Both complexes adopt distorted tetrahedral coordination geometries surrounding the Co(II) center, which is ligated by two doubly deprotonated oxamide ligands oriented perpendicularly to each other. Their axial magnetic anisotropies were revealed by the direct current (dc) magnetic measurements, high-field and high-frequency electron paramagnetic resonance, and theoretical calculations. Both complexes display slow magnetic relaxation in the absence of an applied dc field. Upon the application of the 0.15 T dc field, the quantum tunneling of magnetization is efficiently suppressed. In addition, both complexes display hysteresis loops with different field sweep rates at 1.8 K, which is rarely observed for Co(II) single-ion magnets (SIMs).
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Affiliation(s)
- Hui-Hui Cui
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China
| | - Fang Lu
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology , Nanjing Normal University , Nanjing 210023 , China
| | - Xue-Tai Chen
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China
| | - Yi-Quan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology , Nanjing Normal University , Nanjing 210023 , China
| | - Wei Tong
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions , High Magnetic Field Laboratory of the Chinese Academy of Science , Hefei 230031 , Anhui , China
| | - Zi-Ling Xue
- Department of Chemistry , University of Tennessee , Knoxville , Tennessee 37996 , United States
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7
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Liu X, Su S, Zhu GY, Shu Y, Gao Q, Meng M, Cheng T, Liu CY. Making Use of the δ Electrons in K 4Mo 2(SO 4) 4 for Visible-Light-Induced Photocatalytic Hydrogen Production. ACS APPLIED MATERIALS & INTERFACES 2019; 11:24006-24017. [PMID: 31241882 DOI: 10.1021/acsami.9b03918] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Quadruply bonded dimolybdenum complexes with a σ2π4δ2 electronic configuration for the ground state have rich metal-centered photochemistry. An earlier study showed that stoichiometric or less amount of molecular hydrogen was produced upon irradiation by ultraviolet light (λ = 254 nm) of K4Mo2(SO4)4 in sulfuric acid solution, which was attributed to the reductive capability of the ππ* excited state. To make use of the δ electrons for visible-light-induced photocatalytic hydrogen evolution, a multicomponent heterogeneous photocatalytic system containing K4Mo2(SO4)4 photosensitizer, TiO2 electron relay, and MoS2 cocatalyst is designed and tested. With ascorbic acid added as a sacrificial reagent, irradiation by artificial sunlight (AM 1.5) on the reaction in 5 M H2SO4 has produced 13 400 μmol g-1 of molecular hydrogen (based on the Mo2 complex), which is 30 times higher than the hydrogen yield obtained from the reaction of bare K4Mo2(SO4)4 with H2SO4 under ultraviolet light irradiation. Further improvement of hydrogen evolution is achieved by addition of oxalic acid, along with an electron donor, which gives an additional 50% increase in H2 yield. Spectroscopic analyses indicate that, in this case, a junction between the Mo2 complex and TiO2 is built by the oxalate bridging ligand, which facilitates charge injection and separation from the Mo2 core. This Mo2-TiO2-MoS2 system has achieved a high hydrogen evolution rate up to 4570 μmol g-1 h-1. The efficiency of K4Mo2(SO4)4 as a metal-centered photosensitizer is also proved by parallel experiments with a dye chromophore, fluorescein, which presents comparable H2 yields and hydrogen evolution rates. Most importantly, in this study, detailed analyses illustrate that the photocatalytic cycle with hydrogen gas as an outcome of the reaction is established by involvement of the δδ* excited state generated by visible light irradiation. Therefore, this work shows the potential of quadruply bonded Mo2 complexes as photosensitizers for photocatalytic hydrogen evolution.
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Affiliation(s)
- Xiao Liu
- Department of Chemistry , Jinan University , 601 Huang-Pu Avenue West , Guangzhou 510632 , China
| | - Shaoyang Su
- 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
| | - Yijin Shu
- Department of Chemistry , Jinan University , 601 Huang-Pu Avenue West , Guangzhou 510632 , China
| | - Qingsheng Gao
- 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
| | - Tao Cheng
- 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
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8
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Taher D, Awwadi FF, Al-Noaimi M, Khader LK, Juwhari HK, Amarne H, Kailani MH, Ibdah A. Bis(N,N′-substituted oxamate) Zincate(II) complexes: Synthesis, spectroscopy, solid state structure and DFT calculations. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2019.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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9
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Gao H, Mallick S, Cao L, Meng M, Cheng T, Chen HW, Liu CY. Electronic Coupling and Electron Transfer between Two Mo 2 Units through meta- and para-Phenylene Bridges. Chemistry 2019; 25:3930-3938. [PMID: 30561861 DOI: 10.1002/chem.201805866] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Indexed: 11/09/2022]
Abstract
A series of three Mo2 dimers bridged by a meta-phenylene group has been studied in terms of electronic coupling (EC) and electron transfer (ET) in comparison with the para isomers. Optical analyses on the mixed-valence complexes indicate that by replacing a para-phenylene bridge with a meta one, the EC between the two Mo2 centers is dramatically weakened; consequently, the ET rates (ket ) are lowered by two to three orders of magnitude. In the para series, the EC parameters (Hab ) and ET rates (ket ) are greatly affected by O/S atomic alternation of the bridging ligand. However, for the meta analogues, similar EC and ET parameters are obtained, that is, Hab =300-400 cm-1 and ket ≈109 s-1 . These results suggest that through-σ-bond and/or through-space coupling channels become operative as the π conjugation is disabled. DFT calculations reveal that destructive quantum interference features seen for the meta series arise from the cancellation of two π-conjugated coupling pathways.
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Affiliation(s)
- Hang Gao
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, 510632, P. R. China
| | - Suman Mallick
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, 510632, P. R. China
| | - Lijiu Cao
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, 510632, P. R. China
| | - Miao Meng
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, 510632, P. R. China
| | - Tao Cheng
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, 510632, P. R. China
| | - Huo Wen Chen
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, 510632, P. R. China
| | - Chun Y Liu
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, 510632, P. R. China
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10
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Chen HW, Mallick S, Zou SF, Meng M, Liu CY. Mapping Bridge Conformational Effects on Electronic Coupling in Mo 2-Mo 2 Mixed-Valence Systems. Inorg Chem 2018; 57:7455-7467. [PMID: 29809000 DOI: 10.1021/acs.inorgchem.8b01056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The large bridging ligand 9,10-anthracenedicarboxylate and its thiolated derivatives have been employed to assemble two dimolybdenum complex units and develop three Mo2 dimers, [Mo2(DAniF)3]2(μ-9,10-O2CC14H8CO2), [Mo2(DAniF)3]2(μ-9,10-OSCC14H8COS), and [Mo2(DAniF)3]2(μ-9,10-S2CC14H8CS2) (DAniF = N, N'-di( p-anisyl)formamidinate), for the study of conformation dependence of the electronic coupling between the two Mo2 centers. These compounds feature a large deviation of the central anthracene ring from the plane defined by the Mo-Mo bond vectors, with the torsion angles (ϕ = 50-76°) increasing as the chelating atoms of the bridging ligand vary from O to S. Consequently, the corresponding mixed-valence complexes do not exhibit characteristic intervalence charge transfer absorptions in the near-IR spectra, in contrast to the phenylene and naphthalene analogues, from which these systems are assigned to the Class I in Robin-Day's scheme. Together with the phenylene and naphthalene series, the nine total mixed-valence complexes in three series complete a transition from the electronically uncoupled Class I to the strongly coupled Class II-III borderline via moderately coupled Class II and permit a systematic mapping of the bridge conformation effects on electronic coupling. Density functional theory calculations show that the HOMO-LUMO energy gap, corresponding to the metal (δ) to ligand (π*) transition energy, and the magnitude of HOMO-HOMO-1 splitting in energy are linearly related to cos2 ϕ. Therefore, our experimental and theoretical results concur to indicate that the coupling strength decreases in the order of the bridging units: phenylene > naphthalene > anthracene, which verifies the through-bond superexchange mechanism for electronic coupling and electron transfer.
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Affiliation(s)
- Huo Wen Chen
- Department of Chemistry , Jinan University , 601 Huang-Pu Avenue West , Guangzhou 510632 , China
| | - Suman Mallick
- Department of Chemistry , Jinan University , 601 Huang-Pu Avenue West , Guangzhou 510632 , China
| | - Shan Feng Zou
- 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
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11
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Mallick S, Lu Y, Luo MH, Meng M, Tan YN, Liu CY, Zuo JL. Aromaticity-Driven Molecular Structural Variation and Electronic Configuration Alternation: An Example of Cyclic π Conjugation Involving a Mo-Mo δ Bond. Inorg Chem 2017; 56:14888-14899. [PMID: 29206033 DOI: 10.1021/acs.inorgchem.7b02133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have synthesized and characterized the mixed-ligand dimolybdenum paddlewheel complex Na[(DAniF)3Mo2(C3S5)] (Na[1]; DAniF = N,N'-di-p-anisylformamidinate, dmit = 1,3-dithiole-2-thione-4,5-dithiolate), which has a six-membered chelating [Mo2S2C2] ring created by equatorial coordination of the dmit (C3S5) ligand to the Mo2 unit. One-electron oxidation of Na[1] using Cp2FePF6 yields the neutral complex [(DAniF)3Mo2(C3S5)] ([1]), and removal of two electrons from Na[1] using AgBPh4 gives [(DAniF)3Mo2(C3S5)]BPh4 ([1]BPh4). In the crystal structures, [1]- and [1] present dihedral angles of 118.9 and 142.3° between the plane defined by the Mo-Mo bond vector and the dmit ligand, respectively, while DFT calculations show that in [1]+ the Mo-Mo bond and the dmit ligand are coplanar. Complex [1] is paramagnetic with a g value of 1.961 in the EPR spectrum and has a Mo-Mo bond distance of 2.133(1) Å, increased from 2.0963(9) Å for [1]-. Consistently, a broad absorption band is observed for [1] in the near-IR region, which arises from charge transfer from the dmit ligand to the cationic Mo25+ centers. Interestingly, complex [1]+ has an aromatic [Mo2S2C2] core, as evidenced by a large diamagnetic anisotropy, in addition to the coplanarity of the core structure, which shifts downfield the 1H NMR signal of the horizontal methine proton (ArN-(CH)-NAr) but upfield those of the vertical protons, relative to the methine proton resonances for the precursor ([1]-). The magnetic anisotropy (Δχ = χ⊥ - χ∥) for the [Mo2S2C2] ring in [1]+ is -105.5 ppm cgs, calculated from the McConnell equation, which is about 2-fold larger than that for benzene. The aromaticity of the [Mo2S2C2] ring is supported by theoretical studies, including single-point calculations and gauge-including atomic orbital (GIAO) NMR spectroscopic calculations at the density functional theory (DFT) level. DFT calculations also show that the [Mo2S2C2] core in [1]+ possesses a set of three highest occupied and three lowest unoccupied molecular orbitals in π character, corresponding to those of benzene in symmetry, and six π electrons that conform to the Hückel 4n + 2 rule for aromaticity. Therefore, this study shows that an aromatic [Mo2S2C2] core is formed by coupling the δ orbital of the Mo≣Mo bond with the π orbital of the C═C bond through the bridging atoms (S), thus validating the equivalency in bonding functionality between δ and π orbitals.
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Affiliation(s)
- Suman Mallick
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou-510632, China
| | - Ye Lu
- Department of Chemistry, Tongji University , Shanghai-200092, China
| | - Ming Hui Luo
- 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
| | - Ying Ning Tan
- 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.,Department of Chemistry, Tongji University , Shanghai-200092, China
| | - Jing-Lin Zuo
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing-210023, China
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12
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Ghosh MK, Mandal S, Islam A, Mohapatra S, Chattopadhyay S. Ruthenium-Carbon(Aryl) Bond Cleavage and Change in the Ligand Coordination Mode in a Four-Membered Ortho-Metalated Ruthenium(II) Organometallics Promoted by Thiolato Ligands. ChemistrySelect 2017. [DOI: 10.1002/slct.201701046] [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)
- Mrinal K. Ghosh
- Department of Chemistry; University of Kalyani; Kalyani, Nadia 741235, WB India
| | - Suman Mandal
- Department of Chemistry; University of Kalyani; Kalyani, Nadia 741235, WB India
| | - Anikul Islam
- Department of Chemistry; University of Kalyani; Kalyani, Nadia 741235, WB India
| | - Sudip Mohapatra
- Department of Chemistry; Missouri University of S & T; Rolla, MO 65409 USA
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13
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Chen L, Mallick S, Tan YN, Meng M, Liu CY. Charge Transfer Properties of Triarylamine Integrated Dimolybdenum Dyads. Inorg Chem 2017. [PMID: 28636342 DOI: 10.1021/acs.inorgchem.7b00913] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three quadruply bonded dimolybdenum complexes equipped with a triarylamine pendant, [(DAniF)3Mo2(μ-O2CC6H4N(C6H4CH3)2] (DAniF = N,N'-di(p-anisyl)formamidinate; [OO-ph-N]), [(DAniF)3Mo2(μ-OSCC6H4N(C6H4CH3)2] ([OS-ph-N]), and [(DAniF)3Mo2(μ-S2CC6H4N(C6H4CH3)2] ([SS-ph-N]), have been synthesized and characterized by single crystal X-ray diffraction. In electrochemical measurements, the redox couple for the organic amine group becomes irreversible, reflecting the substantially strong electronic interaction between the dimetal center and organic redox site. The potential difference for the two successive redox events, ca. ΔE1/2(E1/2(2)(N/N•+) - E1/2(1)(Mo2IV/V)), falls in the range of 0.5-0.8 V as estimated from the differential pulse voltammograms. For the monocation radicals [OO-ph-N]+, [OS-ph-N]+, and [SS-ph-N]+, obtained by chemical oxidation of the neutral precursor, a broad ligand (amine) to metal (Mo2) charge transfer (LMCT) absorption band is observed in the near-IR region. Interestingly, analogous to the intervalence charge transfer (IVCT) bands for mixed-valence complexes, the LMCT absorption bands, which are solvent dependent, decrease in energy and bandwidth as the electronic coupling between the two redox sites increases in an order of increasing S content in the chelating group. The electronic coupling matrix elements (Hab) are determined by optical analyses from the generalized Mulliken-Hush (GMH) theory, falling in the range of 400-800 cm-1 in CH2Cl2. These results indicate that in these radical cations the charge is localized. Time-dependent DFT calculations show that the frontier molecular orbitals for these asymmetrical donor-acceptor systems have unbalanced distribution of electron density, and the LMCT bands arise from an electronic transition from the pendant ligand-based to metal-based molecular orbitals, corresponding to donor (N)-acceptor (Mo2) charge transfer.
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Affiliation(s)
- Lu Chen
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou-510632, China
| | - Suman Mallick
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou-510632, China
| | - Ying Ning Tan
- 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
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14
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Mallick S, Cheng T, Chen L, Meng M, Zhang YY, Liu CY. A study of asymmetrical mixed-valent Mo 2-Mo 2 complexes in the class III regime. Dalton Trans 2017; 46:5711-5723. [PMID: 28345709 DOI: 10.1039/c6dt04915j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Three novel asymmetrical dimolybdenum dimers, [Mo2(DAniF)3]2(μ-OOCCOS) (DAniF = N,N'-di(p-anisyl)formamidinate) ([OO-OS]), [Mo2(DAniF)3]2(μ-S2CCO2) ([SS-OO]), and [Mo2(DAniF)3]2(μ-SSCCOS) ([SS-OS]), have been synthesized and characterized by either single-crystal X-ray crystallography or 1H NMR spectroscopy. The structural asymmetry for these compounds gives rise to a redox asymmetry, which enlarges the potential separation (ΔE1/2) between the two [Mo2] units. The mixed-valance (MV) species [OO-OS]+, [SS-OO]+ and [SS-OS]+, prepared by one-electron chemical oxidation of the neutral precursors, exhibit an intense and symmetrical intervalence charge transfer (IVCT) absorption band in the near-IR region, along with the high energy metal (δ) to ligand (π*) (ML) and ligand (π) to metal (δ) charge transfer (LMCT) absorptions. The LMCT band, which is absent in the neutral precursors, is reflective of the cationic [Mo2]+ unit in the MV species; therefore, it is evidenced that in the MV complexes optical electron transfer from the electron donor to acceptor occurs, while the thermal process is energetically unfavorable. The C(1)-C(2) bonds (1.44-1.48 Å) that connect the two [Mo2] units are significantly shorter than a C-C single bond, showing that the two Mo2 centers are strongly coupled. For the series, TD-DFT calculations show that the molecular orbitals have an unsymmetrical charge density distribution over the two dimolybdenum sites. For each of the complex systems, the calculated orbital energy gaps, SOMO(δ - δ)-LUMO(bridging ligand π*), HOMO-8(bridging ligand π)-SOMO(δ - δ) and SOMO(δ - δ)-HOMO-1(δ + δ), are in good agreement with the observed MLCT, LMCT and IVCT absorption band energies, respectively. The consistency in energy between the IVCT band and the SOMO(δ - δ)-HOMO-1(δ + δ) gap permits assignment of the MV complexes to Class III in the Robin-Day scheme.
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Affiliation(s)
- Suman Mallick
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China.
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15
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Lu N, Bu Y. Computational design of three Cu-induced triangular pyrimidines based DNA motifs with improved conductivity. CAN J CHEM 2017. [DOI: 10.1139/cjc-2016-0595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Novel DNA triangular pyrimidine derivatives are designed by metal decoration through replacement of H by Cu in the Watson–Crick hydrogen bond region. The DFT method is used to examine the coordination of triangle-arranged Cu with three pyrimidines in nonplanar three-bladed turbine geometries. The Cu···Cu cuprophilic bonds are ascribed to the partially occupied d orbitals without direct molecular orbital (MO) interactions. Four-center bonds depend on Cu–N/O bonds, which are contributed by p orbitals of N/O atoms along or perpendicular to the bond axis. The activity of frontier MOs is modulated, leading to the decrease of gaps, ionization potentials (IPs), and electron affinities (EAs) desired for the improvement of conductivity. The hole trapping ability is assured by virtue of the spin density distributed on Cu. On average, the single electron density is located on π orbitals of three aromatic base rings. There is paramagnetic electron delocalization on the inner d orbitals of triangle region. The analysis of electron localization function ELF-π and electrostatic potential maps reveals that the outer strong π–π stacking interaction together with the inner d orbital channel enable effective transduction of electrical signals along the Cu–DNA nanowires. The 3Cu-induced triangular pyrimidines have important potential applications as structural motifs of molecular electronic devices.
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Affiliation(s)
- Nan Lu
- College of Chemistry and Material Science, Shandong Agricultural University, Taian, P. R. China, 271018
| | - Yuxiang Bu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, P. R. China, 250100
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16
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Cooke MW, Santoni MP, Loiseau F, Hasenknopf B, Hanan GS. Energy transfer in rhodium–ruthenium dimer-of-dimer assemblies. Inorganica Chim Acta 2017. [DOI: 10.1016/j.ica.2016.05.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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17
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Majumdar M, Saha S, Dutta I, Sinha A, Bera JK. Inter-ligand electronic coupling mediated through a dimetal bridge: dependence on metal ions and ancillary ligands. Dalton Trans 2017; 46:5660-5669. [DOI: 10.1039/c6dt04679g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The metal–metal bond orbitals and the ancillary ligands influence inter-ligand charge transfer through the dimetal bridge.
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Affiliation(s)
- Moumita Majumdar
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Sayantani Saha
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Indranil Dutta
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Arup Sinha
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Jitendra K. Bera
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
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18
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Rej S, Majumdar M, Kando S, Sugino Y, Tsurugi H, Mashima K. Mixed Ligated Tris(amidinate)dimolybdenum Complexes as Catalysts for Radical Addition of CCl4 to 1-Hexene: Leaving Ligand Lability Controls Catalyst Activity. Inorg Chem 2016; 56:634-644. [DOI: 10.1021/acs.inorgchem.6b02525] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Supriya Rej
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Moumita Majumdar
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Shun Kando
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Yoshitaka Sugino
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
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19
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Zhu GY, Meng M, Tan YN, Xiao X, Liu CY. Electronic Coupling between Two Covalently Bonded Dimolybdenum Units Bridged by a Naphthalene Group. Inorg Chem 2016; 55:6315-22. [PMID: 27243960 DOI: 10.1021/acs.inorgchem.6b01021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using 2,6-naphthalenedicarboxylate and its thiolated derivatives as bridging ligands, three Mo2 dimers of the type [Mo2(DAniF)3](E2CC10H6CE2)[Mo2(DAniF)3] (DAniF = N,N'-di-p-anisylformamidinate; E = O, S) have been synthesized and characterized by X-ray diffraction. These compounds can be generally formulated as [Mo2]-naph-[Mo2], where the complex unit [Mo2] ([Mo2(DAniF)3(μ-E2C)]) functions as an electron donor (acceptor) and the naphthalene (naph) group is the bridge. The mixed-valence (MV) complexes, generated by one-electron oxidation of the neutral precursors, display weak, very broad intervalence charge-transfer absorption bands in the near-to-mid-IR regions. The electronic coupling matrix elements for the MV complexes, Hab = 390-570 cm(-1), are calculated from the Mulliken-Hush equation, which fall between those for the phenyl (ph) and biphenyl (biph) analogues reported previously. The three series consisting of three complexes with the same [Mo2] units exhibit exponential decay of Hab as the bridge changes from ph to biph via naph, with decay factors of 0.21-0.17 Å(-1). Therefore, it is evidenced that while the extent of the bridge conjugacy varies, the electronic coupling between the two [Mo2] units is dominated by the Mo2···Mo2 separation. The absorption band energies for metal-to-ligand charge transfer are in the middle of those for the ph and biph analogues, which is consistent with variation of the HOMO-LUMO energy gaps for the complex series. These results indicate that the interplay of the bridge length and conjugacy is to affect the enegy for charge transfer crossing the intervening moiety, in accordance with a superechange mechanism.
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Affiliation(s)
- Guang Yuan Zhu
- 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
| | - Ying Ning Tan
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou 510632, China
| | - Xuan Xiao
- 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
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20
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Lu N, Bu Y, Wang H. Intensified effects of multi-Cu modification on the electronic properties of the modified base pairs containing hetero-ring-expanded pyrimidine bases. Phys Chem Chem Phys 2016; 18:2913-23. [PMID: 26733396 DOI: 10.1039/c5cp06133d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Novel DNA base pair derivatives (A2CunU, A2CunC, G3CunU, and G3CunC) are designed by aromatic expansion of pyrimidine bases with four kinds of hetero-rings (denoted by nC and nU, n = 1, 2, 3, and 4) and metal-decoration through Cu replacement of hydrogens in the Watson-Crick hydrogen bond region. Their structures and properties are calculated for examining the cooperative effects of the two modification ways. The calculated results reveal that multiple Cu decoration makes up the deficiencies of size-expansion, and exhibits not only increase of structural stability and reduction of ionization potentials, but also ideal shrink of the HOMO-LUMO gaps, notable enhancement of interbase coupling as well as remarkable redshifts of π → π* transitions for all M-x modified base pairs. The decrease extents of the gaps and ionization potentials follow the same order G3CunU > G3CunC > A2CunU > A2CunC, and in each series (denoted by different n), the gaps, ionization potentials and first π → π* transition energies have an order of 4 < 1 < 2 < 3. The Cu d orbitals function as bridges for π electron delocalization on the conjugated aromatic rings of two bases, leading to an enhancement of transverse electronic communication, as verified by spin density delocalization, orbital composition changes, redshift of the π → π* transition and also advocated by the electron-sharing indexes such as delocalization index, Mayer bond orders and multicenter bonding. Electron localization function ELF-π isosurfaces above the molecular plane further suggested that effective longitudinal conduction is closely relevant with the bicyclic domain involving good electron delocalization and strong π-π stacking between layers. This work presents theoretical evidence for the cooperative effects of metal decoration and ring-expansion modifications on the electronic properties of the modified base pairs and also proves that the base pairs designed here could be competent building blocks for the DNA-based nanowires with improved electron activity and excellent conductivity.
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Affiliation(s)
- Nan Lu
- College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, P. R. China and School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
| | - Yuxiang Bu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
| | - Huatian Wang
- College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, P. R. China
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21
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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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22
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Cai XM, Meister TK, Pöthig A, Kühn FE. Filling a Gap: Electrochemical Property Comparison of the Completed Compound Series [Mo2(DArF)n(O2C-Fc)4-n] (DArF = N,N'-Diarylformamidinate; O2C-Fc = Ferrocenecarboxylate). Inorg Chem 2016; 55:858-64. [PMID: 26707163 DOI: 10.1021/acs.inorgchem.5b02329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reaction of cis-[Mo2(O2C-Fc)2(NCCH3)4][BF4]2 (cis-1) with two electronically different N,N'-diarylformamidinate (DArF) ligands (DArF = N,N'-bis(p-trifluoromethylphenyl)formamidinate (DTfmpF), N,N'-bis(p-anisyl)formamidinate (DAniF)) results in the isolation of the tris- and monosubstituted complexes [Mo2(DTfmpF)3(O2C-Fc)] (2a) and [Mo2(DAniF)(O2C-Fc)3] (2b). These complexes complete the series of [Mo2(DArF)n(O2C-Fc)4-n] (n = 4-0) type compounds, thus allowing for a comprehensive study. On the basis of the oxidation potential E1/2([Mo2](4+)/[Mo2](5+)) of all Mo2 complexes, ligand basicity is found to decrease in the order DAniF(-) > DTfmpF(-) > Fc-CO2(-) ≫ CH3CN. In addition, no direct electronic interaction between the trans-positioned Fc units in complex 2b is detected, which is attributed to the full overlap of all Fc oxidation processes. Furthermore, the low-energy absorption bands of compounds 2a,b are located at different positions in their respective UV-vis spectra.
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Affiliation(s)
- Xu-Min Cai
- Molecular Catalysis, Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München (TUM) , Lichtenbergstraße 4, 85747 Garching bei München, Germany
| | - Teresa K Meister
- Molecular Catalysis, Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München (TUM) , Lichtenbergstraße 4, 85747 Garching bei München, Germany
| | - Alexander Pöthig
- CRC , Ernst-Otto-Fischer-Straße 1, 85747 Garching bei München, Germany
| | - Fritz E Kühn
- Molecular Catalysis, Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München (TUM) , Lichtenbergstraße 4, 85747 Garching bei München, Germany.,CRC , Ernst-Otto-Fischer-Straße 1, 85747 Garching bei München, Germany
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23
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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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24
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Bridge- and solvent-mediated intramolecular electronic communications in ubiquinone-based biomolecular wires. Sci Rep 2015; 5:10352. [PMID: 25996306 PMCID: PMC4440530 DOI: 10.1038/srep10352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 04/08/2015] [Indexed: 11/18/2022] Open
Abstract
Intramolecular electronic communications of molecular wires play a crucial role for
developing molecular devices. In the present work, we describe different degrees of
intramolecular electronic communications in the redox processes of three
ubiquinone-based biomolecular wires (Bis-CoQ0s) evaluated by
electrochemistry and Density Functional Theory (DFT) methods in different solvents.
We found that the bridges linkers have a significant effect on the electronic
communications between the two peripheral ubiquinone moieties and solvents effects
are limited and mostly depend on the nature of solvents. The DFT calculations for
the first time indicate the intensity of the electronic communications during the
redox processes rely on the molecular orbital elements VL for electron
transfer (half of the energy splitting of the LUMO and LUMO+1), which is could be
affected by the bridges linkers. The DFT calculations also demonstrates the effect
of solvents on the latter two-electron transfer of Bis-CoQ0s is more
significant than the former two electrons transfer as the observed electrochemical
behaviors of three Bis-CoQ0s. In addition, the electrochemistry and
theoretical calculations reveal the intramolecular electronic communications vary in
the four-electron redox processes of three Bis-CoQ0s.
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25
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26
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Dimolybdenum dimers spaced by phenylene groups: The experimental models for study of electronic coupling. Inorganica Chim Acta 2015. [DOI: 10.1016/j.ica.2014.09.039] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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27
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The magic of the delta bonds: How to modulate electronic communication in pairs-of-pairs containing multiple bonded Mo2 species. Inorganica Chim Acta 2015. [DOI: 10.1016/j.ica.2014.03.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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28
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Shu Y, Lei H, Tan YN, Meng M, Zhang XC, Liu CY. Tuning the electronic coupling in Mo2-Mo2 systems by variation of the coordinating atoms of the bridging ligands. Dalton Trans 2014; 43:14756-65. [PMID: 25157859 DOI: 10.1039/c4dt00786g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three novel [Mo2]-bridge-[Mo2] complexes were synthesized by a convergent assembling reaction of the dimetal precursor Mo2(DAniF)3(O2CCH3) (DAniF = N,N'-di(p-anisyl)formamidinate) with the bridging ligands terephthalamidine, terephthalamide and dithioterephthalamide. The structures of these compounds, [Mo2(DAniF)3]2[μ-1,4-{C(E)NH}2-C6H4] (E = NH (), O () or S ()), were determined, either by X-ray crystallography or (1)H NMR spectroscopy, to be the analogues of the terephthalate bridged dimolybdenum dimer. These compounds are structurally and electronically closely related by having the same structural skeleton and similar bonding parameters, which allowed us to analyze the differences between N, O and S atoms on the bridging ligand in promoting electronic interaction between the two [Mo2] units. In the electronic spectra, the metal to ligand charge transfer absorption bands, attributed to the HOMO (dδ) → LUMO (pπ*) transition, was red shifted as the variable atoms change from N to O to S. The mixed-valence species (+), (+) and (+), generated by one-electron oxidation of the neutral precursors and measured in situ, exhibited characteristic intervalence absorption bands, for which the energy and half-height bandwidth decreased from (+) to (+). Therefore, in comparison to O atoms, S atoms are capable of enhancing the electronic coupling between the two [Mo2] units, and the incorporation of N atoms to the bridging ligands slightly diminished the metal-metal interaction. The molecular structures and spectroscopic properties of these compounds were simulated by theoretical calculations at DFT level on the simplified models, which gave results consistent with the experimental observations.
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Affiliation(s)
- Yao Shu
- Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou 510632, China.
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29
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Falvello LR, Foxman BM, Murillo CA. Fitting the Pieces of the Puzzle: The δ Bond. Inorg Chem 2014; 53:9441-56. [DOI: 10.1021/ic500119h] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Larry R. Falvello
- Departamento de Química Inorgánica, ICMA, Universidad de Zaragoza, CSIC, Pedro Cerbuna 12, E-50009 Zaragoza, Spain
| | - Bruce M. Foxman
- Department of Chemistry, MS 015, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Carlos A. Murillo
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
- Department
of Chemistry, University of Texas at El Paso, El Paso, Texas 79968, United States
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30
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Cheng T, Meng M, Lei H, Liu CY. Perturbation of the charge density between two bridged Mo₂ centers: the remote substituent effects. Inorg Chem 2014; 53:9213-21. [PMID: 25119527 DOI: 10.1021/ic501313q] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of terephthalate-bridged dimolybdenum dimers with various formamidinate ancillary ligands, denoted as [Mo2(ArNCHNAr)3]2(μ-O2CC6H4CO2) (Ar = p-XC6H4, with X = OCH3 (1), CH3 (2), F (3), Cl (4), OCF3 (5), and CF3 (6)), has been synthesized and studied in terms of substituent effects on electron delocalization between the two dimetal sites. X-ray structural analyses show that these complexes share the same molecular scaffold with the para-substituents (X) being about 8 Å away from the Mo2 center. It is found that the remote substituents have the capability to tune the electronic properties of the complexes. For the series 1 to 6, the metal-metal bond distances (d(Mo-Mo)) decrease slightly and continuously; the potential separations (ΔE(1/2)) for the two successive one-electron oxidations decrease constantly, and the metal to ligand transition energies (λ(max)) increase in order. More interestingly, the two types of methine protons, H(∥) on the horizontal and H(⊥) on the vertical ligands with respect to the plane defined by the Mo-Mo bond vectors and bridging ligand, display separate resonant signals δ(∥) and δ(⊥) in the NMR spectra. The displacements of the chemical shifts, Δδ(∥-⊥) = δ(∥) - δ(⊥), are getting smaller as the substituents vary from electron-donating to -withdrawing. These results show that the peripheral groups on the [Mo2] units function to fine-tune the metal-metal interactions crossing the bridging ligand. The experimental parameters, ΔE(1/2), λ(max), and Δδ(∥-⊥), which are linearly related with the Hammett constants (σ(X)) of the X groups, can be used to probe the charge density on the two [Mo2] units and the electronic delocalization between them.
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Affiliation(s)
- Tao Cheng
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou 510632, China
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Han LJ, Kong YJ. Pentafluorobenzoato-dimolybdenum(II) Solvate and Co-crystal Complexes with Benzene and Naphthalin. Z Anorg Allg Chem 2014. [DOI: 10.1002/zaac.201400234] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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32
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Tanaka S, Tsurugi H, Mashima K. Supramolecular assemblies of multi-nuclear transition metal complexes: Synthesis and redox properties. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2014.01.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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33
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Brown-Xu SE, Chisholm MH, Durr CB, Lewis SA, Spilker TF, Young PJ. Molybdenum–molybdenum quadruple bonds supported by 9,10-anthraquinone carboxylate ligands. Molecular, electronic, ground state and unusual photoexcited state properties. Chem Sci 2014. [DOI: 10.1039/c4sc00341a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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34
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Gadge ST, Bhanage BM. Recent developments in palladium catalysed carbonylation reactions. RSC Adv 2014. [DOI: 10.1039/c3ra46273k] [Citation(s) in RCA: 253] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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35
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Zhang L, Zhou L, Tian J, Li X. Structural, electronic, and photophysical properties of thieno-expanded tricyclic purine analogs: a theoretical study. Phys Chem Chem Phys 2014; 16:4338-49. [DOI: 10.1039/c3cp54505a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Brown-Xu SE, Chisholm MH, Durr CB, Lewis SA, Spilker TF, Young PJ. Mo2 paddlewheel complexes functionalized with a single MLCT, S1 infrared-active carboxylate reporter ligand: preparation and studies of ground and photoexcited states. Inorg Chem 2013; 53:637-44. [PMID: 24359530 DOI: 10.1021/ic402775s] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
From the reactions between Mo2(DAniF)3pivalate (DAniF = N,N'-di(p-anisyl)formamidinate) and the carboxylic acids LH, the title compounds Mo2(DAniF)3L have been prepared and characterized: compounds I (L = O2CC≡CPh), II (L = O2CC4H2SC≡CH), and III (L = O2CC6H4-p-CN). The new compounds have been characterized in their ground states by spectroscopy ((1)H NMR, ultraviolet-visible absorption, near-infrared absorption, and steady state emission), cyclic voltammetry, and density functional theory calculations. The compounds show strong metal Mo2 to ligand L δ-π* transitions in their visible spectra. The nature of the S1 (1)MLCT and T1 states has been probed by time-resolved (femtosecond and nanosecond) transient absorption and infrared spectroscopy. The observed shifts of the C≡C and C≡N vibrational modes are found to be consistent with the negative charge being localized on the single L in the S1 states, while the T1 states are (3)Mo2 δδ*. The present results are compared to earlier studies of the photoexcited states of trans-Mo2(2,4,6-triisopropylbenzoate)2L2 compounds that have been assigned as either localized or delocalized.
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Affiliation(s)
- Samantha E Brown-Xu
- Department of Chemistry and Biochemistry, The Ohio State University , 100 W. 18th Avenue, Columbus, Ohio 43210, United States
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37
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Xiao X, Liu CY, He Q, Han MJ, Meng M, Lei H, Lu X. Control of the charge distribution and modulation of the class II-III transition in weakly coupled Mo2-Mo2 systems. Inorg Chem 2013; 52:12624-33. [PMID: 24151862 DOI: 10.1021/ic4017855] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three novel dimolybdenum dimers [Mo2(DAniF)3]2(μ-OSCC6H4CSO), [Mo2(DAniF)3]2(μ-O2CC6H4CS2), and [Mo2(DAniF)3]2(μ-S2CC6H4CS2) (DAniF = N,N'-di(p-anisyl)formamidinate) have been synthesized and characterized by single-crystal X-ray diffractions. Together with the terephthalate analogue, the four compounds, denoted as [O2-O2], [OS-OS], [S2-S2], and [O2-S2], have similar molecular skeletons and Mo2···Mo2 separations (∼12 Å), but varying sulfur contents or symmetry. The singly oxidized complexes [O2-O2](+), [OS-OS](+), [S2-S2](+), and [O2-S2](+) display characteristic intervalence transition absorption bands in the near- and mid-IR regions, with differing band energy, intensity, and shape. Applying the geometrical length of the bridging group "-CC6H4C-" (5.8 Å) as the effective electron transfer distance, calculations from the Mulliken-Hush equation yield electronic coupling matrix elements (H(ab)) in the range 600-900 cm(-1). Significantly, this series presents a transition from electron localization to "almost-delocalization" as the carboxylate groups of the bridging ligand are successively thiolated. In terms of Robin-Day's scheme, [S2-S2](+) is best described as an intermediate between Class II and III, while [O2-O2](+) and [OS-OS](+) belong to Class II. It is unusual that the Class II-III transition occurs in such a weakly coupled system (H(ab) < 1000 cm(-1)). This is attributed to the d(δ)-p(π) conjugation between the Mo2 center and bridging ligand. By electrochemical and spectroscopic methods, the internal energy difference for [O2-S2](+) is determined to be 2250 ± 80 cm(-1), which controls the charge distribution of the cation radical. The experimental results and theoretical analyses illustrate that the unsymmetrical geometry leads to unbalanced electronic configurations and asymmetrical redox and optical behaviors.
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Affiliation(s)
- Xuan Xiao
- Department of Chemistry, Tongji University , 1239 Siping Road, Shanghai 200092, China
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38
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Ibarra-Rodríguez M, Rasika Dias HV, Jiménez-Pérez VM, Muñoz-Flores BM, Flores-Parra A, Sánchez S. Dinuclear Tin(II) Complex of a Bulky cis-Oxamide: Synthesis, Characterization, Crystal Structure, and DFT Studies. Z Anorg Allg Chem 2012. [DOI: 10.1002/zaac.201200212] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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39
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Tan ZF, Liu CY, Li Z, Meng M, Weng NS. Abnormally long-range diamagnetic anisotropy induced by cyclic d(δ)-p(π) π conjugation within a six-membered dimolybdenum/chalcogen ring. Inorg Chem 2012; 51:2212-21. [PMID: 22296335 DOI: 10.1021/ic2021947] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Incorporating two quadruply bonded dimolybdenum units [Mo(2)(DAniF)((3))](+) (ancillary ligand DAniF = N,N'-di-p-anisylformamidinate) with two hydroselenides (SeH(-)) gave rise to [Mo(2)(DAniF)(3)](2)(μ-SeH)(2) (1). With the molecular scaffold remaining unchanged, aerobic oxidation of 1, followed by autodeprotonation, generated [Mo(2)(DAniF)(3)](2)(μ-Se)(2) (2). The two complexes share a common cyclic six-membered Mo(2)/Se core, but compound 2 is distinct from 1 by having structural, electronic, and magnetic properties that correspond with aromaticity. Importantly, the aromatic behaviors for this non-carbon system are ascribable to the bonding analogy between the δ component in a Mo-Mo quadruple bond and the π component in a C-C double bond. Cyclic π delocalization via d(δ)-p(π) conjugation within the central unit, which involves six π electrons with one electron from each of the Mo(2) units and two electrons from each of the bridging atoms, has been confirmed in a previous work on the oxygen- and sulfur-bridged analogues (Fang, W.; et al. Chem.-Eur. J.2011, 17, 10288). Of the three members in this family, compound 2 exhibits an enhanced aromaticity because of the selenium bridges. The remote in-plane and out-of-plane methine (ArNCHNAr) protons resonate at chemical shifts (δ) 9.42 and 7.84 ppm, respectively. This NMR displacement, Δδ = 1.58 ppm, is larger than that for the oxygen-bridged (1.30 ppm) and sulfur-bridged (1.49 ppm) derivatives. The abnormally long-range shielding effects and the large diamagnetic anisotropy for this complex system can be rationalized by the induced ring currents circulating the Mo(2)/chalcogen core. By employment of the McConnell equation {Δσ = Δχ[(l - 3 cos 2θ)/3R(3)N]}, the magnetic anisotropy (Δχ = χ(⊥) - χ(||)) is estimated to be -414 ppm cgs, which is dramatically larger than -62.9 ppm cgs for benzene, the paradigm of aromaticity. In addition, it is found that the magnitude of Δχ is linearly related to the radius of the bridging atoms, with the selenium analogue having the largest value. This aromaticity sequence is in agreement with that for the chalcogen-containing aromatic family, e.g., furan < thiophene < selenophene.
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Affiliation(s)
- Zhong Fei Tan
- Department of Chemistry, Tongji University, Shanghai 200092, People's Republic of China
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40
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Li J, Meng S, Zhang J, Song Y, Huang Z, Zhao H, Wei H, Huang W, Cifuentes MP, Humphrey MG, Zhang C. Solvent-induced syntheses of 2D/3D [AgSCN]n-based supramolecular isomers with unusual topologies: structural, theoretical and nonlinear optical studies. CrystEngComm 2012. [DOI: 10.1039/c2ce06610f] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Fang W, He Q, Tan ZF, Liu CY, Lu X, Murillo CA. Experimental and theoretical evidence of aromatic behavior in heterobenzene-like molecules with metal-metal multiple bonds. Chemistry 2011; 17:10288-96. [PMID: 21818792 DOI: 10.1002/chem.201003693] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Indexed: 11/11/2022]
Abstract
Binding two quadruply bonded dimolybdenum units [Mo(2)(DAniF)(3)](+) (DAniF=N,N'-di-p-anisylformamidinate) with two chalcogen atoms generated two molecules with a central core composed of a cyclic six-membered [Mo(2)](2)(μ-EH)(2) species (E=S in 1 and O in 3, and [Mo(2)] is a quadruple-bonded [Mo(2)(formamidinate)(3)] unit). Aerobic oxidation of 1 and 3 followed by concomitant deprotonation gave rise to the corresponding [Mo(2)](2)(μ-E)(2) compounds 2 and 4. The latter show a striking coplanarity and near-bond equalization of the Mo/E cluster. The oxidized species 2 and 4 are diamagnetic in the measured temperature range of 5 to 300 K, which is somewhat unexpected for molecules that have dimetal units with a σ(2)π(4)δ(1) electronic configuration. This suggests there are strong interactions between the dimolybdenum units through the E atoms. The large electronic delocalization of the δ electrons over the entire Mo/E core is supported by the exceptionally large potential separation for the two successive one-electron reductions of the linked Mo(2)(5+) units from the oxidized species (ΔE(½)=1.7 V for the sulfur analogue). This large electronic delocalization has an important effect on the NMR spectroscopic signals for the two sets of methine (N-(CH)-N) protons from the DAniF ligands. Those essentially parallel to the core, H(∥), and those essentially perpendicular to the core, H(⊥), exhibit downfield and upfield chemical shifts, respectively, that are separated by δ=1.32 ppm. The structural, electronic, magnetic, and chemical behaviors for 2 and 4 are consistent with aromaticity, with the [Mo(2)E(2)Mo(2)] cores that resemble the prototypical benzene molecule. Theoretical studies, including DFT calculations, natural bond orbital (NBO) analyses, and gauge-independent atomic orbital (GIAO) NMR spectroscopic calculations, are also consistent with the aromaticity of the [Mo(2)](2)(μ-E)(2) units being promoted by d(δ)(Mo(2))-p(π)(E) π conjugation. The cyclic π conjugation of the central moiety in 2 and 4 involves a total of six electrons with 2e from δ(Mo(2)) and 4e from p(π)(E) orbitals, thereby conforming to Hückel's rule when electrons in the MOs with δ character are considered part of the delocalized system.
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Affiliation(s)
- Wenjuan Fang
- Department of Chemistry, Tongji University, Shanghai, 200092, P.R. China
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42
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Ismayilov RH, Wang WZ, Lee GH, Yeh CY, Hua SA, Song Y, Rohmer MM, Bénard M, Peng SM. Two linear undecanickel mixed-valence complexes: increasing the size and the scope of the electronic properties of nickel metal strings. Angew Chem Int Ed Engl 2011; 50:2045-8. [PMID: 21344548 DOI: 10.1002/anie.201006695] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 12/13/2010] [Indexed: 11/07/2022]
Affiliation(s)
- Rayyat H Ismayilov
- Department of Chemistry, National Taiwan University, 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan, ROC
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43
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Ismayilov RH, Wang WZ, Lee GH, Yeh CY, Hua SA, Song Y, Rohmer MM, Bénard M, Peng SM. Two Linear Undecanickel Mixed-Valence Complexes: Increasing the Size and the Scope of the Electronic Properties of Nickel Metal Strings. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201006695] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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44
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Han LJ. (μ-Benzoato-κO:O')tris-[μ-N,N'-bis-(4-meth-oxy-phen-yl)formamidinato-κN:N']dimolybdenum(II) dichloro-methane monosolvate. Acta Crystallogr Sect E Struct Rep Online 2011; 67:m256. [PMID: 21522909 PMCID: PMC3051605 DOI: 10.1107/s1600536811002558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Accepted: 01/19/2011] [Indexed: 11/29/2022]
Abstract
The title compound, [Mo2(C15H15N2O2)3(C7H5O2)]·CH2Cl2, has a quadruply bonded Mo24+ unit equatorially coordinated by three N,N′-bis(4-μ-methoxyphenyl)formamidinate (DAniF) ligands and one benzoate anion. The Mo—Mo bond length of 2.0881 (8) Å is typical for quadruply bonded species. The phenyl ring and the connected dimetal chelating ring (Mo2O2C) are nearly co-planar, making a dihedral angle of 3.24 (13)°. The dichloromethane solvent molecule is disordered over four sets of sites with occupancies of 0.3:0.3:0.2:0.2.
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Affiliation(s)
- L-J Han
- Department of Chemistry, Tongji University, Shanghai 200092, People's Republic of China
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45
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Electronically Coupled MM Quadruple Bonded Complexes of Molybdenum and Tungsten. STRUCTURE AND BONDING 2010. [DOI: 10.1007/978-3-642-05243-9_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
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46
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Ma JG, Aksu Y, Gregoriades LJ, Sauer J, Driess M. Activation of C–H bonds mediated by MoMo moieties in heterobimetallic Zn/O/Moclusters. Dalton Trans 2010:103-6. [DOI: 10.1039/b917585g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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47
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Cotton FA, Li Z, Murillo CA. Evidence of disruption of conjugation involving delta bonds in intramolecular electronic coupling. Inorg Chem 2009; 48:11847-52. [PMID: 19911818 DOI: 10.1021/ic9018647] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A dimer of dimers containing two quadruply bonded [Mo(2)(DAniF)(3)](+) units (DAniF = N,N'-di(p-anisyl)formamidinate) linked by the S-donor linker, dimethyldithiooxamidate was synthesized, structurally characterized, and electronic communication was probed. The core of [Mo(2)(DAniF)(3)](2)(C(2)S(2)N(2)Me(2)), 1, formed by the Mo(2)NSC(2)SNMo(2) atoms shows two fused but non planar six-membered rings, which differs from that of the beta form of dimethyloxamidate analogue that has a heteronaphthalene-type structure (Cotton, F. A.; Liu, C. Y.; Murillo, C. A.; Villagran, D.; Wang, X. J. Am. Chem. Soc. 2004, 126, 14822). For these two analogous compounds electronic coupling between the two [Mo(2)] units, as determined by electrochemical measurements, diminishes considerably upon replacement of O-donor by S-donor atoms (DeltaE(1/2) = 531 mV and 440 mV, respectively). This suggests that the non planar conformation of the linker in 1 hampers a pathway leading to pi conjugation. Density functional theory (DFT) calculations show that the highest occupied molecular orbitals HOMO-HOMO-1 energy gap of 0.12 eV for 1 is much smaller than that of 0.61 eV for the O-donor analogue, which is consistent with the electrochemical data.
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Affiliation(s)
- F Albert Cotton
- Department of Chemistry, Laboratory for Molecular Structure and Bonding, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012, USA
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48
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Cotton FA, Murillo CA, Zhao Q. Influence of Bonding Mode of the Linkers in the Electronic Communication of Molecular Pairs Having Dimolybdenum Units Linked by Pseudohalides. Inorg Chem 2009; 48:11755-66. [DOI: 10.1021/ic901826y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- F. Albert Cotton
- Department of Chemistry, P.O. Box 3012, Texas A&M University, College Station, Texas 77842-3012
| | - Carlos A. Murillo
- Department of Chemistry, P.O. Box 3012, Texas A&M University, College Station, Texas 77842-3012
| | - Qinliang Zhao
- Department of Chemistry, P.O. Box 3012, Texas A&M University, College Station, Texas 77842-3012
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49
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Han MJ, Liu CY, Tian PF. Enhanced Electronic Coupling in a Molecular Pair of Dimolybdenum Units Bridged by a Tetrathioterephthalate Dianion. Inorg Chem 2009; 48:6347-9. [DOI: 10.1021/ic900956k] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mei Juan Han
- Department of Chemistry, Tongji University, Shanghai 200092, People's Republic of China
| | - Chun Y. Liu
- Department of Chemistry, Tongji University, Shanghai 200092, People's Republic of China
| | - Peng Fei Tian
- Department of Chemistry, Tongji University, Shanghai 200092, People's Republic of China
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50
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Chisholm MH, Singh N. Are tetrathiooxalate and diborinate bridged compounds related to oxalate bridged quadruply bonded compounds of molybdenum? Dalton Trans 2009:5867-72. [DOI: 10.1039/b901734h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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