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Zarandi MA, Pathak P, Beltrami N, Walker JN, Zhang F, Brodbelt JS, Schmehl R, Jayawickramarajah J. Heteromeric guanosine (G)-quadruplex derived antenna modules with directional energy transfer. Nanoscale 2023; 15:19069-19073. [PMID: 37990645 DOI: 10.1039/d3nr04086k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
A heteromeric guanosine (G)-quadruplex centered self-assembly approach is developed to prepare compact light-harvesting antenna modules featuring multiple donor dyes and a single toehold region. Due to the mix-and-match nature of our approach, the number and placement of donor dyes can be readily fine-tuned via quadruplex assembly. Moreover, hybridization of the toehold with an acceptor containing sequence results in directional energy transfer ensembles with effective absorption coefficients in the 105 M-1 cm-1 range. These compact antennas exhibit system efficiencies that are comparable to much larger and elaborate DNA architectures containing numerous DNA strands.
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Affiliation(s)
| | - Pravin Pathak
- Department of Chemistry, Tulane University, New Orleans, LA, 70118, USA.
| | - Noah Beltrami
- Department of Chemistry, Tulane University, New Orleans, LA, 70118, USA.
| | - Jada N Walker
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712, USA
| | - Fengqi Zhang
- Department of Chemistry, Tulane University, New Orleans, LA, 70118, USA.
| | - Jennifer S Brodbelt
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712, USA
| | - Russell Schmehl
- Department of Chemistry, Tulane University, New Orleans, LA, 70118, USA.
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Zhang H, Zhang B, Zhu M, Grayson SM, Schmehl R, Jayawickramarajah J. Water-soluble porphyrin nanospheres: enhanced photo-physical properties achieved via cyclodextrin driven double self-inclusion. Chem Commun (Camb) 2015; 50:4853-5. [PMID: 24686923 DOI: 10.1039/c4cc01372g] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We describe a method to construct water-soluble porphyrinic nanospheres with enhanced photo-physical properties as a result of precluding (via intra-molecular host-guest interactions) the individual porphyrins units from aromatic-aromatic stacking.
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Affiliation(s)
- Hong Zhang
- Department of Chemistry, Tulane University, 2015 Percival Stern Hall, Louisiana 70118, USA.
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Zhu M, Aryal GH, Zhang N, Zhang H, Su X, Schmehl R, Liu X, Hu J, Wei J, Jayawickramarajah J. Host-guest interactions derived multilayer perylene diimide thin film constructed on a scaffolding porphyrin monolayer. Langmuir 2015; 31:578-586. [PMID: 25495000 DOI: 10.1021/la504297w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The development of methods to grow well-ordered chromophore thin films on solid substrates is of importance because such surface-associated arrays have potential applications in the generation of functional electronic and optical materials and devices. In this article, we demonstrate a straightforward layer-by-layer (LBL) supramolecular deposition strategy to prepare numerous layers (up to 19) of functionalized perylene diimide (PDI) chromophores built upon a covalent scaffolding multivalent porphyrin monolayer. Our thin film formation strategy employs water as the immersion solvent and exploits the β-cyclodextrin-adamantane host-guest couple in addition to PDI based aromatic stacking. Within the resultant film the porphyrin scaffold is oriented close to parallel to the glass substrate while the PDI chromophores are aligned closer to the surface normal. Together, the porphyrin monolayer and the multi-PDI layers exhibit a large absorption bandwidth in the visible spectrum. Importantly, because a self-assembly strategy was utilized, when a single monolayer of PDI is deposited on the porphyrin scaffolding layer, this PDI monolayer can be readily disassembled by washing with DMF leading to the regeneration of the porphyrin monolayer. The PDI thin film can subsequently be regrown from the regenerated porphyrin surface. The reported LBL strategy will be of broad interest for researchers developing well-organized chromophoric films and materials due to its simplicity as well as the added advantage of being performed in sustainable and cost-effective aqueous media.
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Affiliation(s)
- Mengyuan Zhu
- Department of Chemistry and ‡Department of Physics & Engineering Physics, Tulane University , New Orleans, Louisiana 70118, United States
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Shan B, Schmehl R. Photochemical Generation of Strong One-Electron Reductants via Light-Induced Electron Transfer with Reversible Donors Followed by Cross Reaction with Sacrificial Donors. J Phys Chem A 2014; 118:10400-6. [DOI: 10.1021/jp503901v] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Bing Shan
- Department
of Chemistry, Tulane University, New Orleans, Louisiana 70118, United States
| | - Russell Schmehl
- Department
of Chemistry, Tulane University, New Orleans, Louisiana 70118, United States
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Fathalla M, Neuberger A, Li SC, Schmehl R, Diebold U, Jayawickramarajah J. Straightforward self-assembly of porphyrin nanowires in water: harnessing adamantane/beta-cyclodextrin interactions. J Am Chem Soc 2010; 132:9966-7. [PMID: 20597548 DOI: 10.1021/ja1030722] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A convenient approach for the self-assembly of well-defined porphyrin nanowires in water, wherein the individual monomers do not aggregate via pi-pi interactions, is disclosed. These unidirectional and heteromeric assemblies are instead composed of robust beta-CD/adamantane host/guest interactions. A combination of surface microscopies and fluorescence energy transfer experiments were conducted on the nanowires demonstrating their stability and resistance to disassembly.
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Affiliation(s)
- Maher Fathalla
- Department of Chemistry, Tulane University, 2015 Percival Stern Hall, Louisiana 70118, USA
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Jarosz P, Lotito K, Schneider J, Kumaresan D, Schmehl R, Eisenberg R. Platinum(II) Terpyridyl-Acetylide Dyads and Triads with Nitrophenyl Acceptors via a Convenient Synthesis of a Boronated Phenylterpyridine. Inorg Chem 2009; 48:2420-8. [DOI: 10.1021/ic801769v] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Paul Jarosz
- Department of Chemistry, University of Rochester, Rochester, New York 14627, and Department of Chemistry, Tulane University, New Orleans, Louisiana 70118
| | - Kenneth Lotito
- Department of Chemistry, University of Rochester, Rochester, New York 14627, and Department of Chemistry, Tulane University, New Orleans, Louisiana 70118
| | - Jacob Schneider
- Department of Chemistry, University of Rochester, Rochester, New York 14627, and Department of Chemistry, Tulane University, New Orleans, Louisiana 70118
| | - Duraisamy Kumaresan
- Department of Chemistry, University of Rochester, Rochester, New York 14627, and Department of Chemistry, Tulane University, New Orleans, Louisiana 70118
| | - Russell Schmehl
- Department of Chemistry, University of Rochester, Rochester, New York 14627, and Department of Chemistry, Tulane University, New Orleans, Louisiana 70118
| | - Richard Eisenberg
- Department of Chemistry, University of Rochester, Rochester, New York 14627, and Department of Chemistry, Tulane University, New Orleans, Louisiana 70118
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Tarr MA, Birdwhistell KR, Birdwhistell TT, Schmehl R. Hurricane Katrina: Impacts at four university chemistry departments in New Orleans. J Chem Health Saf 2007. [DOI: 10.1016/j.jchas.2007.03.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Grassian VH, Meyer G, Abruña H, Coates GW, Achenie LE, Allison T, Brunschwig B, Ferry J, Garcia-Garibay M, Gardea-Torresdey J, Grey CP, Hutchison J, Li CJ, Liotta C, Ragauskas A, Minteer S, Mueller K, Roberts J, Sadik O, Schmehl R, Schneider W, Selloni A, Stair P, Stewart J, Thorn D, Tyson J, Voelker B, White JM, Wood-Black F. Chemistry for a sustainable future. Environ Sci Technol 2007; 41:4840-6. [PMID: 17711191 DOI: 10.1021/es0725798] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Affiliation(s)
- Vick H Grassian
- College of Liberal Arts and Sciences, University of Iowa, USA.
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Yu R, Arumugam K, Manepalli A, Tran Y, Schmehl R, Jacobsen H, Donahue JP. Reversible, Electrochemically Controlled Binding of Phosphine to Iron and Cobalt Bis(dithiolene) Complexes. Inorg Chem 2007; 46:5131-3. [PMID: 17511444 DOI: 10.1021/ic0624569] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The homoleptic bis(dithiolene) complexes [M(S(2)C(2)R(2))(2)](2) (M = Fe, Co; R = p-anisyl) undergo two successive reductions to form anions that display [M(S(2)C(2)R(2))(2)](2)(2-) <--> 2[M(S(2)C(2)R(2))(2)](1-) solution equilibria. The neutral dimers react with Ph3P to form square pyramidal [M(Ph(3)P)(S(2)C(2)R(2))(2)](0). Voltammetric measurements upon [M(Ph(3)P)(S(2)C(2)R(2))(2)](0) in CH(2)Cl(2) reveal only irreversible features at negative potentials, consistent with Ph(3)P dissociation upon reduction. Dissociation and reassociation of Ph(3)P from and to [Fe(Ph(3)P)(S(2)C(2)R(2))(2)](0) is demonstrated by spectroelectrochemical measurements. These collective observations form the basis for a cycle of reversible, electrochemically controlled binding of Ph(3)P to [M(S(2)C(2)R(2))(2)](2) (M = Fe, Co; R = p-anisyl). All members of the cycle ([M(S(2)C(2)R(2))(2)](2)(0), [M(S(2)C(2)R(2))(2)](2)(1-), [MM(S(2)C(2)R(2))(2)](2)(2-), [M(S(2)C(2)R(2))(2)](1-), [M(Ph(3)P)(S(2)C(2)R(2))(2)]) for M = Fe, Co have been characterized by crystallography. Square planar [Fe(S(2)C(2)R(2))(2)](1-) is the first such iron dithiolene species to be structurally identified and reveals Fe-S bond distances of 2.172(1) and 2.179(1) Angstrom, which are appreciably shorter than those in corresponding square planar dianions.
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Affiliation(s)
- Rongmin Yu
- Department of Chemistry, Tulane University, 6400 Freret Street, New Orleans, Louisiana 70118-5698, USA
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Mellace MG, Fagalde F, Katz NE, Hester HR, Schmehl R. Photophysical properties of the photosensitizer [Ru(bpy)2(5-CNphen)]2+ and intramolecular quenching by complexation of Cu(II). J Photochem Photobiol A Chem 2006. [DOI: 10.1016/j.jphotochem.2005.10.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Wang XY, Del Guerzo A, Baitalik S, Simon G, Shaw GB, Chen LX, Schmehl R. The influence of bridging ligand electronic structure on the photophysical properties of noble metal diimine and triimine light harvesting systems. Photosynth Res 2006; 87:83-103. [PMID: 16416049 DOI: 10.1007/s11120-005-9007-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2005] [Accepted: 07/04/2005] [Indexed: 05/06/2023]
Abstract
This manuscript discusses the photophysical behavior of transition metal complexes of Ru(II) and Os(II) employed in development of light harvesting arrays of chromophores. Particular emphasis is placed on the relationship between the photophysical behavior of complexes having metal-to-ligand charge transfer (MLCT) excited states and the electronic characteristics of bridging ligands used in preparing oligometallic complexes. Examples are presented that discuss intramolecular energy migration in complexes having two distinct MLCT chromophores with bridging ligands that only very weakly couple the two chromophores. In addition, systems having bridging ligands with localized triplet excited states lower in energy than the MLCT state of the metal center to which they are attached are discussed. These systems very often have excited states localized on the bridging ligand with excited state lifetimes on the order of tens of microseconds. Finally, systems having Fe(II) metal centers, with very low energy MLCT states, are discussed. In complexes also containing bridging ligands with low energy triplet states, energy partitioning between the Fe center MLCT state (or Fe localized ligand field states) and the ligand triplet state is observed; the two states relax to the ground state via parallel pathways, but the Fe(II) center does not serve as an absolute excitation energy sink.
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Affiliation(s)
- Xian-yong Wang
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
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Cattaneo M, Fagalde F, Katz NE, Leiva AM, Schmehl R. Enhancement of Metal−Metal Coupling at a Considerable Distance by Using 4-Pyridinealdazine as a Bridging Ligand in Polynuclear Complexes of Rhenium and Ruthenium. Inorg Chem 2005; 45:127-36. [PMID: 16390048 DOI: 10.1021/ic051312b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Novel polynuclear complexes of rhenium and ruthenium containing PCA (PCA = 4-pyridinecarboxaldehyde azine or 4-pyridinealdazine or 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene) as a bridging ligand have been synthesized as PF(6-) salts and characterized by spectroscopic, electrochemical, and photophysical techniques. The precursor mononuclear complex, of formula [Re(Me(2)bpy)(CO)(3)(PCA)](+) (Me(2)bpy = 4,4'-dimethyl-2,2'-bipyridine), does not emit at room temperature in CH(3)CN, and the transient spectrum found by flash photolysis at lambda(exc) = 355 nm can be assigned to a MLCT (metal-to-ligand charge transfer) excited state [(Me(2)bpy)(CO)(3)Re(II)(PCA(-))](+), with lambda(max) = 460 nm and tau < 10 ns. The spectral properties of the related complexes [[Re(Me(2)bpy)(CO)(3)}(2)(PCA)](2+), [Re(CO)(3)(PCA)(2)Cl], and [Re(CO)(3)Cl](3)(PCA)(4) confirm the existence of this low-energy MLCT state. The dinuclear complex, of formula [(Me(2)bpy)(CO)(3)Re(I)(PCA)Ru(II)(NH(3))(5)](3+), presents an intense absorption in the visible spectrum that can be assigned to a MLCT d(pi)(Ru) --> pi(PCA); in CH(3)CN, the value of lambda (max) = 560 nm is intermediate between those determined for [Ru(NH(3))(5)(PCA)](2+) (lambda(max) = 536 nm) and [(NH(3))(5)Ru(PCA)Ru(NH(3))(5)](4+) (lambda(max) = 574 nm), indicating a significant decrease in the energy of the pi-orbital of PCA. The mixed-valent species, of formula [(Me(2)bpy)(CO)(3)Re(I)(PCA)Ru(III)(NH(3))(5)](4+), was obtained in CH(3)CN solution, by bromine oxidation or by controlled-potential electrolysis at 0.8 V in a OTTLE cell of the [Re(I),Ru(II)] precursor; the band at lambda(max) = 560 nm disappears completely, and a new band appears at lambda(max) = 483 nm, assignable to a MMCT band (metal-to-metal charge transfer) Re(I) --> Ru(III). By using the Marcus-Hush formalism, both the electronic coupling (H(AB)) and the reorganization energy (lambda) for the metal-to-metal intramolecular electron transfer have been calculated. Despite the considerable distance between both metal centers (approximately 15.0 Angstroms), there is a moderate coupling that, together with the comproportionation constant of the mixed-valent species [(NH(3))(5)Ru(PCA)Ru(NH(3))(5)](5+) (K(c) approximately 10(2), in CH(3)CN), puts into evidence an unusual enhancement of the metal-metal coupling in the bridged PCA complexes. This effect can be accounted for by the large extent of "metal-ligand interface", as shown by DFT calculations on free PCA. Moreover, lambda is lower than the driving force -DeltaG degrees for the recombination charge reaction [Re(II),Ru(II)] --> [Re(I),Ru(III)] that follows light excitation of the mixed-valent species. It is then predicted that this reverse reaction falls in the Marcus inverted region, making the heterodinuclear [Re(I),Ru(III)] complex a promising model for controlling the efficiency of charge-separation processes.
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Affiliation(s)
- Mauricio Cattaneo
- Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, (T4000INI) San Miguel de Tucumán, Argentina
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Chakraborty S, Wadas TJ, Hester H, Schmehl R, Eisenberg R. Platinum Chromophore-Based Systems for Photoinduced Charge Separation: A Molecular Design Approach for Artificial Photosynthesis. Inorg Chem 2005; 44:6865-78. [PMID: 16180842 DOI: 10.1021/ic0505605] [Citation(s) in RCA: 170] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photoinduced charge separation is a fundamental step in photochemical energy conversion. In the design of molecularly based systems for light-to-chemical energy conversion, this step is studied through the construction of two- and three-component systems (dyads and triads) having suitable electron donor and acceptor moieties placed at specific positions on a charge-transfer chromophore. The most extensively studied chromophores in this regard are ruthenium(II) tris(diimine) systems with a common 3MLCT excited state, as well as related ruthenium(II) bis(terpyridyl) systems. This Forum contribution focuses on dyads and triads of an alternative chromophore, namely, platinum(II) di- and triimine systems having acetylide ligands. These d8 chromophores all possess a 3MLCT excited state in which the lowest unoccupied molecular orbital is a pi orbital on the heterocyclic aromatic ligand. The excited-state energies of these Pt(II) chromophores are generally higher than those found for the ruthenium(II) tris(diimine) systems, and the directionality of the charge transfer is more certain. The first platinum diimine bis(arylacetylide) triad, constructed by attaching phenothiazene donors to the arylacetylide ligands and a nitrophenyl acceptor to 5-ethynylphenanthroline of the chromophore, exhibited a charge-separated state of 75-ns duration. The first Pt(tpy)(arylacetylide)+-based triad contains a trimethoxybenzamide donor and a pyridinium acceptor and has been structurally characterized. The triad has an edge-to-edge separation between donor and acceptor fragments of 27.95 Angstroms. However, while quenching of the emission is complete for this system, transient absorption (TA) studies reveal that charge transfer does not move onto the pyridinium acceptor. A new set of triads described in detail here and having the formula [Pt(NO2phtpy)(p-C triple-bond C-C6H4CH2(PTZ-R)](PF6), where NO2phtpy = 4'-{4-[2-(4-nitrophenyl)vinyl]phenyl}-2,2';6',2''-terpyridine and PTZ = phenothiazine with R = H, OMe, possess an unsaturated linkage between the chromophore and a nitrophenyl acceptor. While the parent chromophore [Pt(ttpy)(C triple-bond CC6H5)]PF6 is brightly luminescent in a fluid solution at 298 K, the triads exhibit complete quenching of the emission, as do the related donor-chromophore (D-C) dyads. Electrochemically, the triads and D-C dyads exhibit a quasi-reversible oxidation wave corresponding to the PTZ ligand, while the R = H triad and related C-A dyad display a facile quasi-reversible reduction assignable to the acceptor. TA spectroscopy shows that one of the triads possesses a long-lived charge-separated state of approximately 230 ns.
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Affiliation(s)
- Soma Chakraborty
- Department of Chemistry, University of Rochester, New York 14627, USA
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Chakraborty S, Wadas TJ, Hester H, Flaschenreim C, Schmehl R, Eisenberg R. Synthesis, Structure, Characterization, and Photophysical Studies of a New Platinum Terpyridyl-Based Triad with Covalently Linked Donor and Acceptor Groups. Inorg Chem 2005; 44:6284-93. [PMID: 16124807 DOI: 10.1021/ic050688m] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new terpyridyl-containing Pt triad [Pt(pytpy)(p-CC-C6H4-NH-CO-C6H2(OMe)3)](PF6)2 (4), where pytpy = 4'-(4-pyridin-1-ylmethylphenyl)-[2,2';6',2' ']terpyridine and p-CC-C6H4-NH-CO-C6H2(OMe)3 = N-(4-ethynylphenyl)-3,4,5-trimethoxybenzamide, has been synthesized and structurally characterized. The related donor-chromophore dyad [Pt(ttpy)(p-CC-C6H4-NH-CO-C6H2(OMe)3)]PF6 2, where ttpy = 4'-p-tolyl-[2,2';6',2' ']terpyridine, and the chromophore-acceptor dyad [Pt(pytpy)(CCC6H5)](PF6)2 (3), where CCC6H5 = ethynylbenzene, have also been studied. The multistep syntheses culminate with a CuI-catalyzed coupling reaction of the respective acetylene with either [Pt(ttpy)Cl]PF6 or [Pt(pytpy)Cl](PF6)2. X-ray and spectroscopic studies support assignment of a distorted square planar environment around the Pt(II) ion with three of its coordination sites occupied by the terpyridyl N-donors and the fourth coordination site occupied by the acetylenic carbon. Although the parent compound [Pt(ttpy)(CCC6H5)]PF6 (1) is brightly luminescent in fluid solution at 298 K, dyad 2 as well as triad 4 exhibit complete quenching of the emission. The chromophore-acceptor (C-A) dyad 3 displays weak solution luminescence at room temperature with a phi(rel)(em) of 0.011 (using Ru(bpy)3(2+) as a standard with phi(rel)(em) = 0.062). Electrochemically, the donor-chromophore (D-C) dyad and the donor-chromophore-acceptor (D-C-A) triad exhibit both metal-based and donor ligand-based oxidations, whereas the triad and the C-A dyad show the expected pyridinium- and terpyridine-based reductions. Transient absorption studies of the dyad and triad systems indicate that although the trimethoxybenzene group acts as a reductive donor, in the present system, the pyridinium group fails to act as an acceptor.
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Affiliation(s)
- Soma Chakraborty
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
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Surridge NA, Sosnoff CS, Schmehl R, Facci JS, Murray RW. Electron and counterion diffusion constants in mixed-valent polymeric osmium bipyridine films. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100054a029] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Colaneri MJ, Kevan L, Schmehl R. An electron spin resonance study of charge separation in frozen sodium dodecyl sulfate micellar solutions containing tris(2,2'-bipyridine)ruthenium(II) complexes and alkylmethylviologens. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100338a076] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ikeda T, Schmehl R, Denisevich P, Willman K, Murray RW. Permeation of electroactive solutes through ultrathin polymeric films on electrode surfaces. J Am Chem Soc 2002. [DOI: 10.1021/ja00374a001] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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