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Sonoda Y. Chain-Length-Dependent Photophysical Properties of α,ω-Di(4-pyridyl)polyenes: Effects of Solvent Polarity, Hydrogen Bond Formation, Protonation, and N-Alkylation. J Fluoresc 2021; 32:95-108. [PMID: 34562204 DOI: 10.1007/s10895-021-02824-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/08/2021] [Indexed: 11/24/2022]
Abstract
In this study, we investigated the solvent effects on the photophysical properties of α,ω-di(4-pyridyl)polyenes 1-5 having 1-5 double bonds. The solution photoproperties depend strongly on conjugation chain length. The absorption maximum (λa) of dipyridylethylene 1 is observed at around 290 nm and only slightly redshifts as the solvent polarity increases, whereas its fluorescence maximum (λf) redshifts from 368 nm in hexane to 403 nm in acetonitrile. Although 1 is a centrosymmetric molecule, its fluorescence energy linearly correlates with the Onsager solvent polarity function f(ε) - f(n2) = (ε - 1)/(2ε + 1)-(n2 - 1)/(2n2 + 1), indicating that the emission originates from an intramolecular charge transfer (CT) excited state. Exceptionally, λf in methanol is largely blue-shifted to 341 nm from those in other aprotic solvents. The fluorescence solvatochromism of longer polyenes 2-5 is much less significant than that of 1. Upon protonation and N-alkylation, both the absorption and fluorescence spectra of all five compounds are red-shifted in methanol. The largest shifts in λa and λf on protonation are observed for pentaene 5 (73 nm) and diene 2 (57 nm), respectively.
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Affiliation(s)
- Yoriko Sonoda
- Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1, 305-8565, Tsukuba, Ibaraki, Japan.
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2
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Noga K, Romańczyk PP, Włodarczyk AJ, Broclawik E. Theoretical modeling of electrochemical interactions in bimetallic molybdenum nitrosyl complexes incorporating saturated bridges. Polyhedron 2008. [DOI: 10.1016/j.poly.2008.06.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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3
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Electrochemical interactions in binuclear molybdenum and tungsten nitrosyl complexes incorporating saturated n-alkanediolate bridging ligands. Crystal structures of [Mo(NO)(TpMe2)I{O(CH2)2OCOCH3}] and [W(NO)(TpMe2)I2]·0.5I2·0.5C6H5CH3. Polyhedron 2008. [DOI: 10.1016/j.poly.2007.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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4
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Organometallic Chemistry of Polypyridine Ligands I. ADVANCES IN HETEROCYCLIC CHEMISTRY 2007. [DOI: 10.1016/s0065-2725(06)93004-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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5
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Liu SQ, Ning GL, Zhang XF, Konaka H, Munakata M. Crystal Structure of an Octanuclear Sandwich Cluster of Silver(I) and 4,4′-Bis(2,5-dimethylstyryl)biphenyl†. CHINESE J CHEM 2006. [DOI: 10.1002/cjoc.200690234] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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6
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Schwab PFH, Smith JR, Michl J. Synthesis and Properties of Molecular Rods. 2. Zig-Zag Rods. Chem Rev 2005; 105:1197-279. [PMID: 15826013 DOI: 10.1021/cr040707u] [Citation(s) in RCA: 170] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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7
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Yuan P, Liu SH, Xiong W, Yin J, Yu GA, Sung HY, Williams ID, Jia G. Synthesis and Characterization of (CHCH)3-Bridged Heterobimetallic Ferrocene−Ruthenium Complexes. Organometallics 2005. [DOI: 10.1021/om0490637] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ping Yuan
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Sheng Hua Liu
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Weicheng Xiong
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Jun Yin
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Guang-ao Yu
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Ho Yung Sung
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Ian D. Williams
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Guochen Jia
- Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
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8
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Liu SQ, Kuroda-Sowa T, Konaka H, Suenaga Y, Maekawa M, Mizutani T, Ning GL, Munakata M. Silver(I) Coordination Polymers of Fluorescent Oligo(phenylenevinylene) with π−π Stackings: Luminescence and Conductivity. Inorg Chem 2005; 44:1031-6. [PMID: 15859283 DOI: 10.1021/ic0400585] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three luminescent silver(I)-oligo(phenylenevinylene) complexes, [Ag2(bmsb)(ClO4)2] (1), [Ag2(bmsb)(H2O)4](BF4)2 (2), and [Ag2(bdb)(CF3SO3)2] (3) (bmsb = 1, 4-bis(methylstyryl)benzene, bdb = 4,4'-bis(2, 5-dimethylstryryl)biphenyl), have been synthesized and structurally characterized. Complexes 1 and 2 are 2D networks with unique metallocyclophane motifs. Complex 3 affords a 2D zigzag sheet, in which silver triflates form tubelike double chains and bdb molecules act as linkages. Complex 2 exhibits high electric conductivity because of columnar aromatic stackings formed through intra- and intermolecular pi-pi interactions. Complexes 1-3 in the solid state exhibit luminescence, of which excitation and emission maxima are shifted to longer wavelength as compared to those of the corresponding metal-free ligands.
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Affiliation(s)
- Shu Qin Liu
- Department of Chemistry, Kinki University, Higashi-Osaka, Osaka 577-8502, Japan
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Kuo CK, Chang JC, Yeh CY, Lee GH, Wang CC, Peng SM. Synthesis, structures, magnetism and electrochemical properties of triruthenium–acetylide complexes. Dalton Trans 2005:3696-701. [PMID: 16258622 DOI: 10.1039/b506267e] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of triruthenium complexes with arylacetylide axial ligands Ru(3)(dpa)(4)(C(2)X)(2)(BF(4))(y)(dpa = dipyridylamido; X = Fc, y= 0 (1); X = Ph, y= 0 (2); X = PhOCH(3), y= 1 (3); X = PhC(5)H(11), y= 1 (4); X = PhCN, y= 0 (5); X = PhNO(2), y= 0 (6)) have been synthesized. The crystal structures show that the Ru-Ru bond lengths (2.3304(9)-2.3572(5)A) of these compounds are longer than those of Ru(3)(dpa)(4)Cl(2)(Ru-Ru=2.2537(1)A). This is ascribed to the formation of the stronger pi-backbonding from metal to axial ligand which weakens the Ru-Ru interactions and the bond order is reduced in the triruthenium unit. Cyclic voltammetry and differential pulse voltammetry show that compound exhibits electronic coupling between the two ferrocenyl units with DeltaE(1/2) close to 100 mV. Compounds 2-6 display three triruthenium-based reversible one-electron redox couples, two oxidations and one reduction, and the electrode potentials shift upon varying the substituents. A linear relationship is observed when the Hammett constants are plotted against the redox potentials.
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Affiliation(s)
- Ching-Kuo Kuo
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
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10
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Cotton FA, Donahue JP, Murillo CA. Polyunsaturated dicarboxylate tethers connecting dimolybdenum redox and chromophoric centers: syntheses, structures, and electrochemistry. J Am Chem Soc 2003; 125:5436-50. [PMID: 12720458 DOI: 10.1021/ja029101i] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Compounds with two quadruply bonded Mo(2)(4+) units, Mo(2)(DAniF)(3) (DAniF = N,N '-di-p-anisylformamidinate), linked by unsaturated dicarboxylate dianions of various lengths have been prepared and their spectroscopic and electrochemical properties studied. As identified by the dicarboxylate linkers, these compounds are maleate (7), allene-1,3-dicarboxylate (10), cis,cis-muconate (11), trans,trans-muconate (12), octa-2,4,6-trans,trans,trans-hexatriene-1,8-dioate (tamuate, 13), and deca-2,4,6,8-trans,trans,trans,trans-octatetraene-1,10-dioate (texate, 14). The latter three molecules complete the five-membered (all trans) series [Mo(2)(DAniF)(3)](O(2)C(CH=CH)(n)CO(2))[Mo(2)(DAniF)(3)] (n = 0-4). Several unsymmetrical paddlewheel compounds of the type Mo(2)(DAniF)(3)(O(2)CX) (X = C triple bond CH (3), CH=CH(2) (4), (E)-CH=CH-CH=CH(2) (5)) have also been prepared for comparison to the molecules in which there are linked Mo(2) units. The precursors [Mo(2)(DAniF)(3)(MeCN)(2)](BPh(4)), [1]BPh(4), and Mo(2)(DAniF)(3)Cl(MeCN) (2) have also been isolated and characterized. The structures of all new molecules have been established by X-ray crystallography, including the methyl esters of various carboxylates used as ligands. All of the linked molecules have been examined by cyclic and differential pulse voltammetry, and deltaE(1/2) values, the separation between successive Mo(2)(4+)/Mo(2)(5+) oxidations, have been determined. Those compounds with highly unsaturated, fully conjugated linkers demonstrate electrochemical communication from end-to-end that is more persistent over distance than is accounted for by an electrostatic interaction alone, implying that the pi system of these dicarboxylate linkers is mediating communication. In the series [Mo(2)(DAniF)(3)](O(2)C(CH=CH)(n)CO(2))[Mo(2)(DAniF)(3)] (n = 0-4), the first oxidation potential shifts progressively to less positive values due to an increasing contribution of the polyolefinic alpha,omega-dicarboxylate to the molecular orbital undergoing oxidation. This first oxidation potential approaches a limiting value of 63 mV (vs Ag/AgCl) as n becomes infinitely long. Compound 11 can be photoisomerized to 12 in a process that is affected by the presence of the Mo(2)(4+) units, as the analogous rearrangement of dimethyl cis,cis-muconate is faster.
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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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11
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Zhong JC, Munakata M, Maekawa M, Kuroda-Sowa T, Suenaga Y, Konaka H. Syntheses and structural studies on silver(I) coordination polymers with trans,trans-1,4-dipenyl-1,3-butadiene. Inorganica Chim Acta 2003. [DOI: 10.1016/s0020-1693(02)01147-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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12
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Liu SH, Chen Y, Wan KL, Wen TB, Zhou Z, Lo MF, Williams ID, Jia G. Synthesis and Characterization of Linear (CH)8-Bridged Bimetallic Ruthenium Complexes. Organometallics 2002. [DOI: 10.1021/om020442e] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sheng Hua Liu
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Yihui Chen
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Kam Lok Wan
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Ting Bin Wen
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Zhongyuan Zhou
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Man Fung Lo
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Ian D. Williams
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Guochen Jia
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
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13
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Joshi HK, Inscore FE, Schirlin JT, Dhawan IK, Carducci MD, Bill TG, Enemark JH. Six-coordinate molybdenum nitrosyls with a single ene-1,2-dithiolate ligand. Inorganica Chim Acta 2002. [DOI: 10.1016/s0020-1693(02)01127-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Innocent or guilty? Redox activity in and magnetic and optical behaviour of dinuclear molydenum complexes. J CHEM SCI 2002. [DOI: 10.1007/bf02703822] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Ruthenium complexes with 2,2′-, 2,4′- and 4,4′-bipyridine ligands: The role of bipyridine coordination modes and halide ligands. J Organomet Chem 2002. [DOI: 10.1016/s0022-328x(02)01408-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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16
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Syntheses, redox and UV–Vis spectroelectrochemical properties of mono- and dinuclear tris(pyrazolyl)borato-oxomolybdenum(IV) complexes with pyridine ligands. Inorganica Chim Acta 2002. [DOI: 10.1016/s0020-1693(01)00698-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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A novel 2-D silver(I)–acyclic polyene coordination polymer assembled with linear unsaturated bridges. Inorganica Chim Acta 2001. [DOI: 10.1016/s0020-1693(01)00581-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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McCleverty JA, Ward MD, Jones CJ. Redox-Activity in Complexes with Mo(NO) and Mo(O) Cores: Facts and Consequences. COMMENT INORG CHEM 2001. [DOI: 10.1080/02603590108050873] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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19
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Dembinski R, Bartik T, Bartik B, Jaeger M, Gladysz JA. Toward Metal-Capped One-Dimensional Carbon Allotropes: Wirelike C6−C20 Polyynediyl Chains That Span Two Redox-Active (η5-C5Me5)Re(NO)(PPh3) Endgroups. J Am Chem Soc 2000. [DOI: 10.1021/ja992747z] [Citation(s) in RCA: 350] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Roman Dembinski
- Contribution from the Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, and Institut für Organische Chemie, Friedrich-Alexander Universität Erlangen-Nürnberg, Henkestrasse 42, 91054 Erlangen, Germany
| | - Tamás Bartik
- Contribution from the Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, and Institut für Organische Chemie, Friedrich-Alexander Universität Erlangen-Nürnberg, Henkestrasse 42, 91054 Erlangen, Germany
| | - Berit Bartik
- Contribution from the Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, and Institut für Organische Chemie, Friedrich-Alexander Universität Erlangen-Nürnberg, Henkestrasse 42, 91054 Erlangen, Germany
| | - Monika Jaeger
- Contribution from the Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, and Institut für Organische Chemie, Friedrich-Alexander Universität Erlangen-Nürnberg, Henkestrasse 42, 91054 Erlangen, Germany
| | - J. A. Gladysz
- Contribution from the Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, and Institut für Organische Chemie, Friedrich-Alexander Universität Erlangen-Nürnberg, Henkestrasse 42, 91054 Erlangen, Germany
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20
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Synthesis of novel symmetrical and nonsymmetrical 6-membered heterocycles with pendant electron-rich organoiron substituents. Chem Heterocycl Compd (N Y) 1999. [DOI: 10.1007/bf02251798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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21
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Redox active organoiron alkynyl centers with a coordination site: an approach toward molecular plugs. Complexation reactions with (THF)W(CO)5 and (PhCN)2MCl2 (M=Pd, Pt). Inorganica Chim Acta 1999. [DOI: 10.1016/s0020-1693(99)00135-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Briel O, Sünkel K, Krossing I, Nöth H, Schmälzlin E, Meerholz K, Bräuchle C, Beck W. Synthesis and Nonlinear Optical Properties of Carbonylrhenium Bromide Complexes with Conjugated Pyridines. Eur J Inorg Chem 1999. [DOI: 10.1002/(sici)1099-0682(199903)1999:3<483::aid-ejic483>3.0.co;2-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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23
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Deboronation of HB(3,5-Me2C3HN2)3− in a reaction with [Re(O)Cl4]−, the X-ray crystal structures of [{Re(O)Cl(3,5-Me2C3HN2H)3}(μ-O){Re(O)Cl3(3,5-Me2C3HN2H)}] and [{Re(O)Cl2(3,5-Me2C3HN2H)2}(μ-O){Re(O)Cl2(3,5-Me2C3HN2H)2}]. Inorganica Chim Acta 1999. [DOI: 10.1016/s0020-1693(98)00305-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Humphrey ER, An Ung V, Maher JP, McCleverty JA, Ward MD. Bimetallic mixed oxidation state complexes derived by coupling nitrosyl- and oxo-molybdenum cores. J Organomet Chem 1999. [DOI: 10.1016/s0022-328x(98)00653-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Ung VÂ VÂ, Cargill Thompson AMW, Bardwell DA, Gatteschi D, Jeffery JC, McCleverty JA, Totti F, Ward MD. Roles of Bridging Ligand Topology and Conformation in Controlling Exchange Interactions between Paramagnetic Molybdenum Fragments in Dinuclear and Trinuclear Complexes. Inorg Chem 1997; 36:3447-3454. [PMID: 11670020 DOI: 10.1021/ic9610086] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The magnetic properties of two series of dinuclear complexes, and one trinuclear complex, have been examined as a function of the bridging pathway between the metal centers. The first series of dinuclear complexes is [{Mo(V)(O)(Tp)Cl}(2)(&mgr;-OO)], where "OO" is [1,4-O(C(6)H(4))(n)O](2)(-) (n = 1, 1; n = 2, 3), [4,4'-O(C(6)H(3)-2-Me)(2)O](2)(-) (4), or [1,3-OC(6)H(4)O](2)(-) (2) [Tp = tris(3,5-dimethylpyrazolyl)hydroborate]. The second series of dinuclear complexes is [{Mo(I)(NO)(Tp)Cl}(2)(&mgr;-NN)], where "NN" is 4,4'-bipyridyl (5), 3,3'-dimethyl-4,4'-bipyridine (6), 3,8-phenanthroline (7), or 2,7-diazapyrene (8). The trinuclear complex is [{Mo(V)(O)(Tp)Cl}(3)(1,3,5-C(6)H(3)O(3))] (9), whose crystal structure was determined [9.5CH(2)Cl(2): C(56)H(81)B(3)Cl(13)Mo(3)N(18)O(6); monoclinic, P2(1)/n; a = 13.443, b = 41.46(2), c = 14.314(6) Å; beta = 93.21(3) degrees; V = 7995(5) Å(3); Z = 4; R(1) = 0.106]. In these complexes, the sign and magnitude of the exchange coupling constant J is clearly related to both the topology and the conformation of the bridging ligand [where J is derived from H = -JS(1)().S(2)() for 1-8 and H = -J(S(1)().S(2)() + S(2)().S(3)() + S(1)().S(3)()) for 9]. The values are as follows: 1, -80 cm(-)(1); 2, +9.8 cm(-)(1); 3, -13.2 cm(-)(1); 4, -2.8 cm(-)(1); 5, -33 cm(-)(1); 6, -3.5 cm(-)(1); 7, -35.6 cm(-)(1); 8, -35.0 cm(-)(1); 9, +14.4 cm(-)(1). In particular the following holds: (1) J is negative (antiferromagnetic exchange) across the para-substituted bridges ligands of 1 and 3-8 but positive (ferromagnetic exchange) across the meta-substituted bridging ligands of 2 and 9. (2) J decreases in magnitude dramatically as the bridging ligand conformation changes from planar to twisted (compare 3 and 4, or 6 and 8). These observations are consistent with a spin-polarization mechanism for the exchange interaction, propagated across the pi-system of the bridging ligand by via overlap of bridging ligand p(pi) orbitals with the d(pi) magnetic orbitals of the metals. The EPR spectrum of 9 is characteristic of a quartet species and shows weak Deltam(s) = 2 and Deltam(s) = 3 transitions at one-half and one-third, respectively, of the field strength of the principal Deltam(s) = 1 component.
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Affiliation(s)
- V&acaron;n Ân Ung VÂ
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K., and Department of Chemistry, University of Florence, Via Maragliano 75/77, 50144 Florence, Italy
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27
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Lin JT, Wu JJ, Li CS, Wen YS, Lin KJ. Conjugated Pyridines with an End-Capping Ferrocene. Organometallics 1996. [DOI: 10.1021/om960607h] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jiann T. Lin
- Institute of Chemistry, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China
| | - Jiann Jung Wu
- Institute of Chemistry, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China
| | - Chyi-Shiun Li
- Institute of Chemistry, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China
| | - Yuh S. Wen
- Institute of Chemistry, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China
| | - Kuan-Jiuh Lin
- Institute of Chemistry, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China
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