51
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Zhang B, Li Y, Sun W. Anion-Sensitive 2,4-Dinitrophenylhydrazone-Containing Terpyridine Derivative and Its Platinum Chloride Complex. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201100537] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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52
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Li Y, Tam AYY, Wong KMC, Li W, Wu L, Yam VWW. Synthesis, Characterization, and the Photochromic, Luminescence, Metallogelation and Liquid-Crystalline Properties of Multifunctional Platinum(II) Bipyridine Complexes. Chemistry 2011; 17:8048-59. [DOI: 10.1002/chem.201003738] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 04/02/2011] [Indexed: 11/12/2022]
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53
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Chen Z, Wong KMC, Kwok ECH, Zhu N, Zu Y, Yam VWW. Electrogenerated Chemiluminescence of Platinum(II) Alkynyl Terpyridine Complex with Peroxydisulfate as Coreactant. Inorg Chem 2011; 50:2125-32. [DOI: 10.1021/ic101119q] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Zuofeng Chen
- Institute of Molecular Functional Material and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China
| | - Keith Man-Chung Wong
- Institute of Molecular Functional Material and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China
| | - Eric Chi-Ho Kwok
- Institute of Molecular Functional Material and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China
| | - Nianyong Zhu
- Institute of Molecular Functional Material and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China
| | - Yanbing Zu
- Institute of Molecular Functional Material and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China
| | - Vivian Wing-Wah Yam
- Institute of Molecular Functional Material and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China
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Kui SCF, Law YC, Tong GSM, Lu W, Yuen MY, Che CM. Spectacular luminescent behaviour of tandem terpyridyl platinum(ii) acetylide complexes attributed to solvent effect on ordering of excited states, “ion-pair” formation and molecular conformations. Chem Sci 2011. [DOI: 10.1039/c0sc00427h] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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55
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Yam VWW, Wong KMC. Luminescent metal complexes of d6, d8 and d10 transition metal centres. Chem Commun (Camb) 2011; 47:11579-92. [DOI: 10.1039/c1cc13767k] [Citation(s) in RCA: 433] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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56
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Canty AJ, Sharma M. η1-Alkynyl Chemistry for the Higher Oxidation States of Palladium and Platinum. TOP ORGANOMETAL CHEM 2011. [DOI: 10.1007/978-3-642-17429-2_5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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57
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Shiu HY, Wong MK, Che CM. “Turn-on” FRET-based luminescent iridium(iii) probes for the detection of cysteine and homocysteine. Chem Commun (Camb) 2011; 47:4367-9. [DOI: 10.1039/c0cc04288a] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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58
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Chan CKM, Tao CH, Li KF, Wong KMC, Zhu N, Cheah KW, Yam VWW. Design, synthesis, characterization, luminescence and non-linear optical (NLO) properties of multinuclear platinum(ii) alkynyl complexes. Dalton Trans 2011; 40:10670-85. [DOI: 10.1039/c1dt10784d] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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59
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Kwok ECH, Chan MY, Wong KMC, Lam WH, Yam VWW. Functionalized Alkynylplatinum(II) Polypyridyl Complexes for Use as Sensitizers in Dye-Sensitized Solar Cells. Chemistry 2010; 16:12244-54. [DOI: 10.1002/chem.201001424] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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60
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Wang P, Leung CH, Ma DL, Yan SC, Che CM. Structure-based design of platinum(II) complexes as c-myc oncogene down-regulators and luminescent probes for G-quadruplex DNA. Chemistry 2010; 16:6900-11. [PMID: 20437426 DOI: 10.1002/chem.201000167] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A series of platinum(II) complexes with tridentate ligands was synthesized and their interactions with G-quadruplex DNA within the c-myc gene promoter were evaluated. Complex 1, which has a flat planar 2,6-bis(benzimidazol-2-yl)pyridine (bzimpy) scaffold, was found to stabilize the c-myc G-quadruplex structure in a cell-free system. An in silico G-quadruplex DNA model has been constructed for structure-based virtual screening to develop new Pt(II)-based complexes with superior inhibitory activities. By using complex 1 as the initial structure for hit-to-lead optimization, bzimpy and related 2,6-bis(pyrazol-3-yl)pyridine (dPzPy) scaffolds containing amine side-chains emerge as the top candidates. Six of the top-scoring complexes were synthesized and their interactions with c-myc G-quadruplex DNA have been investigated. The results revealed that all of the complexes have the ability to stabilize the c-myc G-quadruplex. Complex 3 a ([Pt(II)L2R](+); L2=2,6-bis[1-(3-piperidinepropyl)-1H-enzo[d]imidazol-2-yl]pyridine, R=Cl) displayed the strongest inhibition in a cell-free system (IC(50)=2.2 microM) and was 3.3-fold more potent than that of 1. Complexes 3 a and 4 a ([Pt(II)L3R](+); L3=2,6-bis[1-(3-morpholinopropyl)-1H-pyrazol-3-yl]pyridine, R=Cl) were found to effectively inhibit c-myc gene expression in human hepatocarcinoma cells with IC(50) values of approximately 17 microM, whereas initial hit 1 displayed no significant effect on gene expression at concentrations up to 50 microM. Complexes 3 a and 4 a have a strong preference for G-quadruplex DNA over duplex DNA, as revealed by competition dialysis experiments and absorption titration; 3 a and 4 a bind G-quadruplex DNA with binding constants (K) of approximately 10(6)-10(7) dm(3) mol(-1), which are at least an order of magnitude higher than the K values for duplex DNA. NMR spectroscopic titration experiments and molecular modeling showed that 4 a binds c-myc G-quadruplex DNA through an external end-stacking mode at the 3'-terminal face of the G-quadruplex. Intriguingly, binding of c-myc G-quadruplex DNA by 3 b is accompanied by an increase of up to 38-fold in photoluminescence intensity at lambda(max)=622 nm.
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Affiliation(s)
- Ping Wang
- Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong, PR China
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61
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Ventura B, Barbieri A, Barigelletti F, Diring S, Ziessel R. Energy Transfer Dynamics in Multichromophoric Arrays Engineered from Phosphorescent PtII/RuII/OsII Centers Linked to a Central Truxene Platform. Inorg Chem 2010; 49:8333-46. [DOI: 10.1021/ic1008413] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Barbara Ventura
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche (ISOF-CNR), Via P. Gobetti 101, 40129 Bologna, Italy
| | - Andrea Barbieri
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche (ISOF-CNR), Via P. Gobetti 101, 40129 Bologna, Italy
| | - Francesco Barigelletti
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche (ISOF-CNR), Via P. Gobetti 101, 40129 Bologna, Italy
| | - Stéphane Diring
- Laboratoire de Chimie Organique et Spectroscopies Avancées (LCOSA), Ecole de Chimie, Polymères, Matériaux (ECPM), Université de Strasbourg (UdS), 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
| | - Raymond Ziessel
- Laboratoire de Chimie Organique et Spectroscopies Avancées (LCOSA), Ecole de Chimie, Polymères, Matériaux (ECPM), Université de Strasbourg (UdS), 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
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62
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Yi J, Zhang B, Shao P, Li Y, Sun W. Synthesis and Photophysics of Platinum(II) 6-Phenyl-4-(9,9-dihexylfluoren-2-yl)-2,2′-bipyridine Complexes with Phenothiazinyl Acetylide Ligand. J Phys Chem A 2010; 114:7055-62. [DOI: 10.1021/jp103639x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Jing Yi
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108-6050
| | - Bingguang Zhang
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108-6050
| | - Pin Shao
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108-6050
| | - Yunjing Li
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108-6050
| | - Wenfang Sun
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108-6050
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63
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Zhao L, Wong KC, Li B, Li W, Zhu N, Wu L, Yam VW. Luminescent Amphiphilic 2,6-Bis(1-alkylpyrazol-3-yl)pyridyl Platinum(II) Complexes: Synthesis, Characterization, Electrochemical, Photophysical, and Langmuir-Blodgett Film Formation Studies. Chemistry 2010; 16:6797-809. [DOI: 10.1002/chem.201000210] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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64
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Pritchett TM, Sun W, Zhang B, Ferry MJ, Li Y, Haley JE, Mackie DM, Shensky W, Mott AG. Excited-state absorption of a bipyridyl platinum(II) complex with alkynyl-benzothiazolylfluorene units. OPTICS LETTERS 2010; 35:1305-1307. [PMID: 20436550 DOI: 10.1364/ol.35.001305] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The singlet excited-state lifetime of a bipyridyl platinum(II) complex containing two alkynyl-benzothiazolylfluorene units was determined to be 145+/-105 ps by fitting femtosecond transient difference absorption data, and the triplet quantum yield was measured to be 0.14. A ground-state absorption cross section of 6.1 x 10(-19) cm(2) at 532 nm was deduced from UV-visible absorption data. Excited-state absorption cross sections of (6.7+/-0.1) x 10(-17) cm(2) (singlet) and (4.6+/-0.1) x 10(-16) cm(2) (triplet) were obtained by using a five-level dynamic model to fit open-aperture Z scans at picosecond and nanosecond pulse widths and a variety of pulse energies. For this complex, the ratio of the triplet excited-state absorption cross section to the ground-state absorption cross section--long used as a figure of merit for reverse saturable absorbers--thus stands at 754, to our knowledge the largest ever reported at 532 nm wavelength.
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Affiliation(s)
- Timothy M Pritchett
- U. S. Army Research Laboratory, RDRL-SEE-M, 2800 Powder Mill Road, Adelphi, Maryland 20783-1197, USA.
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65
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Ji Z, Li S, Li Y, Sun W. Back-to-back dinuclear platinum terpyridyl complexes: synthesis and photophysical studies. Inorg Chem 2010; 49:1337-46. [PMID: 20092284 DOI: 10.1021/ic9009674] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Two back-to-back terpyridine ligands using fluorenyl as bridging group (1-L and 2-L) and their corresponding dinuclear platinum(II) complexes (1 and 2) were synthesized and characterized. Their electronic absorption, photoluminescence, and the triplet transient difference absorption were systematically investigated. Both ligands possess intense (1)pi,pi* absorption in the UV region, and they exhibit structured (1)pi,pi* fluorescence around 400 nm. With addition of p-toluenesulfonic acid to the ligands, both the absorption band and the emission band are red-shifted because of the increased electron-withdrawing ability of the protonated terpyridines and possible mixture of some intraligand charge transfer (ILCT) character. For complexes 1 and 2, they both exhibit broad and strong absorption between 400 and 500 nm, which is assigned as the (1)pi,pi*/(1)ILCT/(1)MLCT (metal-to-ligand charge transfer) transition. The involvement of (1)ILCT in the lowest excited state is evident by the acid titration experiment of the ligands. At room temperature, the complexes exhibit dual emission that admixes fluorescence and phosphorescence from the (1,3)pi,pi*/(1,3)ILCT/(1,3)MLCT states. The assignment of the emitting states is based on the distinct emission lifetimes, different sensitivity to oxygen quenching, and different temperature dependency. Both complexes exhibit emission at 77 K, which is assigned as the mixture of (3)pi,pi*/(3)MLCT. 1 and 2 also exhibit two triplet excited-state absorption bands in the visible to the NIR region, which are tentatively attributed to the (3)pi,pi* and (3)MLCT/(3)ILCT state. In addition, the connection pattern between the fluorenyl component and the terpyridyl components influences the excited-state characteristics of both the ligands and the complexes. Ligand 1-L and its corresponding platinum complex 1 that have the triplet bond connection between the fluorenyl and terpyridyl components exhibit a red-shifted low-energy absorption band, an emission band, and a transient absorption band compared to ligand 2-L and complex 2 that have the fluorenyl directly attached to terpyridyl components. These differences could be rationalized by the enhanced conjugation between the fluorenyl and terpyridyl components in 1-L and 1 because of the better coplanarity induced by the triple bond.
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Affiliation(s)
- Zhiqiang Ji
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58108-6050, USA
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66
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Tong G, Law YC, Kui S, Zhu N, Leung KH, Phillips DL, Che CM. Ligand-to-Ligand Charge-Transfer Transitions of Platinum(II) Complexes with Arylacetylide Ligands with Different Chain Lengths: Spectroscopic Characterization, Effect of Molecular Conformations, and Density Functional Theory Calculations. Chemistry 2010; 16:6540-54. [DOI: 10.1002/chem.200903046] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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67
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Sjöqvist J, Linares M, Norman P. Platinum(II) and Phosphorus MM3 Force Field Parametrization for Chromophore Absorption Spectra at Room Temperature. J Phys Chem A 2010; 114:4981-7. [DOI: 10.1021/jp911046u] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Jonas Sjöqvist
- Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Mathieu Linares
- Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Patrick Norman
- Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden
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68
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Wang KW, Chen JL, Cheng YM, Chung MW, Hsieh CC, Lee GH, Chou PT, Chen K, Chi Y. Mono- versus Dinuclear Pt(II) 6-(5-Trifluoromethyl-Pyrazol-3-yl)-2,2′-Bipyridine Complexes: Synthesis, Characterization, and Remarkable Difference in Luminescent Properties. Inorg Chem 2010; 49:1372-83. [DOI: 10.1021/ic9011313] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kang-Wei Wang
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Jing-Lin Chen
- Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan
- School of Material and Chemistry Engineering, Jiangxi University of Science and Technology, Ganzhou, Jiangxi, 341000, China
| | - Yi-Ming Cheng
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Min-Wen Chung
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Cheng-Chih Hsieh
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Gene-Hsiang Lee
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Kellen Chen
- Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan
| | - Yun Chi
- Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan
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69
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Nastasi F, Puntoriero F, Campagna S, Olivier JH, Ziessel R. Hybrid complexes: Pt(ii)-terpyridine linked to various acetylide-bodipy subunits. Phys Chem Chem Phys 2010; 12:7392-402. [DOI: 10.1039/c003789c] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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70
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Larew NA, Van Wassen AR, Wetzel KE, Machala MM, Cummings SD. Solution luminescence from chloro(2,2′:6′,2″-terpyridine)platinum(II) chloride in micelles. Inorganica Chim Acta 2010. [DOI: 10.1016/j.ica.2009.09.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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71
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Mathew I, Sun W. Photophysics in solution and Langmuir–Blodgett film and vapochromic behavior of the Pt(ii) 2,6-bis(N-alkylbenzimidazol-2′-yl)pyridine complexes with different alkyl chains and counter anions. Dalton Trans 2010; 39:5885-98. [DOI: 10.1039/b923203f] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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72
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Mathew I, Li Y, Li Z, Sun W. Dinuclear platinum(ii) 4,6-diphenyl-2,2′-bipyridine complexes tethered by a rigid bridging ligand: synthesis and photophysics in solution and in LB film. Dalton Trans 2010; 39:11201-9. [DOI: 10.1039/c0dt00597e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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73
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Garner KL, Parkes LF, Piper JD, Williams JAG. Luminescent Platinum Complexes with Terdentate Ligands Forming 6-Membered Chelate Rings: Advantageous and Deleterious Effects in N∧N∧N and N∧C∧N-Coordinated Complexes. Inorg Chem 2009; 49:476-87. [DOI: 10.1021/ic9016323] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Louise F. Parkes
- Department of Chemistry, University of Durham, Durham DH1 3LE, U.K
| | - Jason D. Piper
- Department of Chemistry, University of Durham, Durham DH1 3LE, U.K
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74
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Ji Z, Li Y, Sun W. Acid/base sensitive platinum terpyridyl complex: Switching between metal-to-ligand charge transfer (MLCT), ligand-to-ligand charge transfer (LLCT), and intraligand charge transfer (ILCT) states. J Organomet Chem 2009. [DOI: 10.1016/j.jorganchem.2009.09.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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75
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Muro ML, Diring S, Wang X, Ziessel R, Castellano FN. Photophysics in Platinum(II) Bipyridylacetylides. Inorg Chem 2009; 48:11533-42. [DOI: 10.1021/ic901036a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Maria L. Muro
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403
| | - Stéphane Diring
- Laboratoire de Chimie Organique et Spectroscopies Avancées, associé au Centre National de la Recherche Scientifique (LCM-CNRS), Ecole de Chimie, Polymères, Matériaux (ECPM), 25 rue Becquerel, 67087 Strasbourg Cedex, France
| | - Xianghuai Wang
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403
| | - Raymond Ziessel
- Laboratoire de Chimie Organique et Spectroscopies Avancées, associé au Centre National de la Recherche Scientifique (LCM-CNRS), Ecole de Chimie, Polymères, Matériaux (ECPM), 25 rue Becquerel, 67087 Strasbourg Cedex, France
| | - Felix N. Castellano
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403
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77
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Tam AYY, Wong KMC, Zhu N, Wang G, Yam VWW. Luminescent alkynylplatinum(II) terpyridyl metallogels stabilized by Pt...Pt, pi-pi, and hydrophobic-hydrophobic interactions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:8685-8695. [PMID: 19499924 DOI: 10.1021/la804326c] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A series of luminescent alkynylplatinum(II) terpyridyl complexes have been synthesized and characterized by 1H NMR, IR, FAB-mass spectrometry, and elemental analysis; one of the platinum(III) complexes has also been structurally characterized by X-ray crystallography. Their electrochemical and photophysical properties have also been investigated. A majority of the complexes were able to form stable thermoreversible metallogels in organic solvents, tested by the "stable-to-inversion of a test tube" method. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) of the xerogels showed typical fibrous structures on the micrometer scale. Interestingly, whereas 2-OTf, 3-OTf, and 5-PF6 formed thermotropic metallogels mainly through van der Waals' forces with different emission colors, 1-X (X = OTf, BF4, PF6, and ClO4) showed additional Pt...Pt and pi-pi interactions to stabilize the resultant metallogels and showed drastic color changes during the gel-to-sol phase transition. The metallogels of 1-X were also different colors, depending on the nature of the counter anions, which governs the degree of aggregation and the extent of Pt...Pt and pi-pi interactions involved in the gelation process. This property may be utilized to serve as an effective reporter for microenvironmental changes.
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Affiliation(s)
- Anthony Yiu-Yan Tam
- Centre for Carbon-Rich Molecular and Nano-Scale Metal-Based Materials Research and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong
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78
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Ventura B, Barbieri A, Zanelli A, Barigelletti F, Seneclauze JB, Diring S, Ziessel R. Excited-State Dynamics in a Dyad Comprising Terpyridine-Platinum(II) Ethynylene Linked to Pyrrolidino-[60]Fullerene. Inorg Chem 2009; 48:6409-16. [DOI: 10.1021/ic900069r] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Barbara Ventura
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche (ISOF-CNR), Via P. Gobetti 101, 40129 Bologna, Italy
| | - Andrea Barbieri
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche (ISOF-CNR), Via P. Gobetti 101, 40129 Bologna, Italy
| | - Alberto Zanelli
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche (ISOF-CNR), Via P. Gobetti 101, 40129 Bologna, Italy
| | - Francesco Barigelletti
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche (ISOF-CNR), Via P. Gobetti 101, 40129 Bologna, Italy
| | - Julie Batcha Seneclauze
- Laboratoire de Chimie Organique et Spectroscopies Avancées, Ecole de Chimie, Polymères, Matériaux (ECPM), Université de Strasbourg, 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
| | - Stéphane Diring
- Laboratoire de Chimie Organique et Spectroscopies Avancées, Ecole de Chimie, Polymères, Matériaux (ECPM), Université de Strasbourg, 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
| | - Raymond Ziessel
- Laboratoire de Chimie Organique et Spectroscopies Avancées, Ecole de Chimie, Polymères, Matériaux (ECPM), Université de Strasbourg, 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
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79
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Cummings SD. Platinum complexes of terpyridine: Interaction and reactivity with biomolecules. Coord Chem Rev 2009. [DOI: 10.1016/j.ccr.2008.12.009] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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80
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Mackay FS, Farrer NJ, Salassa L, Tai HC, Deeth RJ, Moggach SA, Wood PA, Parsons S, Sadler PJ. Synthesis, characterisation and photochemistry of Pt(IV) pyridyl azido acetato complexes. Dalton Trans 2009:2315-25. [PMID: 19290364 PMCID: PMC2933821 DOI: 10.1039/b820550g] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pt(II) azido complexes [Pt(bpy)(N(3))(2)] (1), [Pt(phen)(N(3))(2)] (2) and trans-[Pt(N(3))(2)(py)(2)] (3) incorporating the bidentate diimine ligands 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen) or the monodentate pyridine (py) respectively, have been synthesised from their chlorido precursors and characterised by X-ray crystallography; complex 3 shows significant deviation from square-planar geometry (N(3)-Pt-N(3) angle 146.7 degrees ) as a result of steric congestion at the Pt centre. The novel Pt(IV) complexes trans, cis-[Pt(bpy)(OAc)(2)(N(3))(2)] (), trans, cis-[Pt(phen)(OAc)(2)(N(3))(2)] (), trans, trans, trans-[Pt(OAc)(2)(N(3))(2)(py)(2)] (), were obtained from via oxidation with H(2)O(2) in acetic acid followed by reaction of the intermediate with acetic anhydride. Complexes 4-6 exhibit interesting structural and photochemical properties that were studied by X-ray, NMR and UV-vis spectroscopy and TD-DFT (time-dependent density functional theory). These Pt(IV) complexes exhibit greater absorption at longer wavelengths (epsilon = 9756 M(-1) cm(-1) at 315 nm for 4 ; epsilon = 796 M(-1) cm(-1) at 352 nm for 5 ; epsilon = 16900 M(-1) cm(-1) at 307 nm for 6 , in aqueous solution) than previously reported Pt(IV) azide complexes, due to the presence of aromatic amines, and 4-6 undergo photoactivation with both UVA (365 nm) and visible green light (514 nm). The UV-vis spectra of complexes 4-6 were calculated using TD-DFT; the nature of the transitions contributing to the UV-vis bands provide insight into the mechanism of production of the observed photoproducts. The UV-vis spectra of 1-3 were also simulated by computational methods and comparison between Pt(II) and Pt(IV) electronic and structural properties allowed further elucidation of the photochemistry of 4-6.
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Affiliation(s)
- Fiona S. Mackay
- School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK
| | - Nicola J. Farrer
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Luca Salassa
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Hui-Chung Tai
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Robert J. Deeth
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Stephen A. Moggach
- School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK
| | - Peter A. Wood
- School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK
| | - Simon Parsons
- School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK
| | - Peter J. Sadler
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
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81
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Zhang H, Zhang B, Li Y, Sun W. Acid-Sensitive Pt(II) 2,6-Di(pyridin-2-yl)pyrimidin-4(1H)-one Complexes. Inorg Chem 2009; 48:3617-27. [DOI: 10.1021/ic801919g] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hui Zhang
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58108-6050, and Coordination Chemistry Institute and State Key Laboratory, Nanjing University, Nanjing 210093, P.R. China
| | - Bingguang Zhang
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58108-6050, and Coordination Chemistry Institute and State Key Laboratory, Nanjing University, Nanjing 210093, P.R. China
| | - Yunjing Li
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58108-6050, and Coordination Chemistry Institute and State Key Laboratory, Nanjing University, Nanjing 210093, P.R. China
| | - Wenfang Sun
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58108-6050, and Coordination Chemistry Institute and State Key Laboratory, Nanjing University, Nanjing 210093, P.R. China
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82
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Shao P, Li Y, Azenkeng A, Hoffmann MR, Sun W. Influence of Alkoxyl Substituent on 4,6-Diphenyl-2,2′-bipyridine Ligand on Photophysics of Cyclometalated Platinum(II) Complexes: Admixing Intraligand Charge Transfer Character in Low-Lying Excited States. Inorg Chem 2009; 48:2407-19. [DOI: 10.1021/ic801589q] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Pin Shao
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516, Energy and Environmental Research Center, University of North Dakota, Grand Forks, North Dakota 58202-9018, and Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202-9024
| | - Yunjing Li
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516, Energy and Environmental Research Center, University of North Dakota, Grand Forks, North Dakota 58202-9018, and Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202-9024
| | - Alexander Azenkeng
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516, Energy and Environmental Research Center, University of North Dakota, Grand Forks, North Dakota 58202-9018, and Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202-9024
| | - Mark R. Hoffmann
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516, Energy and Environmental Research Center, University of North Dakota, Grand Forks, North Dakota 58202-9018, and Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202-9024
| | - Wenfang Sun
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516, Energy and Environmental Research Center, University of North Dakota, Grand Forks, North Dakota 58202-9018, and Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202-9024
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83
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84
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Chen Z, Wong KMC, Au VKM, Zu Y, Yam VWW. Electrogenerated chemiluminescence of a bis-cyclometalated alkynylgold(iii) complex with irreversible oxidation using tri-n-propylamine as co-reactant. Chem Commun (Camb) 2009:791-3. [DOI: 10.1039/b820400d] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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85
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Okazaki R, Masaoka S, Sakai K. Photo-hydrogen-evolving activity of chloro(terpyridine)platinum(ii): a single-component molecular photocatalyst. Dalton Trans 2009:6127-33. [DOI: 10.1039/b905610f] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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86
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Tang RPL, Wong KMC, Zhu N, Yam VWW. Luminescence, electrochemistry and host–guest properties of dinuclear platinum(ii) terpyridyl complexes of sulfur-containing bridging ligands. Dalton Trans 2009:3911-22. [DOI: 10.1039/b821264c] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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87
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Yam VWW, Hu Y, Chan KHY, Chung CYS. Reversible pH- and solvent-responsive micelle-mediated self-assembly of platinum(ii) terpyridyl-based metallo-supramolecular diblock copolymers. Chem Commun (Camb) 2009:6216-8. [DOI: 10.1039/b911657e] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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88
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Eryazici I, Newkome GR. Construction of hexanuclear macrocycles by a coupling strategy from polyfunctionalized bis(terpyridines). NEW J CHEM 2009. [DOI: 10.1039/b811607e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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89
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Rachford AA, Hua F, Adams CJ, Castellano FN. [Pt(mesBIAN)(tda)]: A near-infrared emitter and singlet oxygen sensitizer. Dalton Trans 2009:3950-4. [DOI: 10.1039/b818177b] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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90
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She C, Rachford AA, Wang X, Goeb S, El-Ballouli AO, Castellano FN, Hupp JT. Solvent-induced configuration mixing and triplet excited-state inversion: insights from transient absorption and transient dc photoconductivity measurements. Phys Chem Chem Phys 2009; 11:8586-91. [DOI: 10.1039/b908977b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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91
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92
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Zhu MX, Lu W, Zhu N, Che CM. Structures and Solvatochromic Phosphorescence of Dicationic Terpyridyl-Platinum(II) Complexes with Foldable Oligo(ortho-phenyleneethynylene) Bridging Ligands. Chemistry 2008; 14:9736-46. [DOI: 10.1002/chem.200800394] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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93
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Meier M, Görls H, Walther D. Lumineszente Eisen-Platin-Mehrkernkomplexe mit funktionalisierten Acetyliden. Z Anorg Allg Chem 2008. [DOI: 10.1002/zaac.200800193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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94
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Ji Z, Li Y, Sun W. 4′-(5′′′-R-Pyrimidyl)-2,2′:6′,2′′-terpyridyl (R = H, OEt, Ph, Cl, CN) Platinum(II) Phenylacetylide Complexes: Synthesis and Photophysics. Inorg Chem 2008; 47:7599-607. [DOI: 10.1021/ic800358w] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhiqiang Ji
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105
| | - Yunjing Li
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105
| | - Wenfang Sun
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105
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95
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Eryazici I, Moorefield CN, Newkome GR. Square-planar Pd(II), Pt(II), and Au(III) terpyridine complexes: their syntheses, physical properties, supramolecular constructs, and biomedical activities. Chem Rev 2008; 108:1834-95. [PMID: 18543874 DOI: 10.1021/cr0781059] [Citation(s) in RCA: 488] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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96
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Muro ML, Diring S, Wang X, Ziessel R, Castellano FN. Photophysics of the platinum(II) terpyridyl terpyridylacetylide platform and the influence of Fe(II) and Zn(II) coordination. Inorg Chem 2008; 47:6796-803. [PMID: 18605689 DOI: 10.1021/ic800316x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The synthesis, structural characterization, and photoluminescence (PL) properties of the square-planar terpyridylplatinum(II) complex [ ( t )Bu 3tpyPtCCtpy] (+) ( 1) and the octahedral trinuclear Fe (II) and Zn (II) analogues [Fe( ( t )Bu 3tpyPtCCtpy) 2] (4+) ( 2) and [Zn( ( t )Bu 3tpyPtCCtpy) 2] (4+) ( 3) are described. The photophysical properties of the mononuclear Pt (II) complex 1 are consistent with a charge-transfer excited-state parentage producing a large Stokes shift with a concomitant broad, structureless emission profile. The Fe-based ligand-field states in 2 provide an efficient nonradiative deactivation pathway for excited-state decay, resulting in a nonemissive compound at room temperature. Interestingly, upon chelation of 1 with Zn (II), a higher energy charge-transfer emission with a low-energy shoulder and a 215 ns excited-state lifetime is produced in 3. A spectroscopically identical species relative to 3 was produced in control experiments when 1 was reacted with excess protons (HClO 4) as ascertained by UV-vis and static PL spectra measured at room temperature and 77 K. Therefore, the chelation of Zn (II) to 1 is acid-base in nature, and its Lewis acidity renders the highest occupied molecular orbital level in 1 much less electron-rich, which induces a blue shift in both the absorption and emission spectra. At 77 K, complexes 1, 3, and protonated 1 display at least one prevalent vibronic component in the emission profile (1360 cm (-1)) resembling PL emanating from a ligand-localized excited-state, indicating that these emitting states are inverted relative to room temperature. These results are qualitatively confirmed by the application of time-dependent theory using only the 1360 cm (-1) mode to reproduce the low-temperature emission spectra.
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Affiliation(s)
- Maria L Muro
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA
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97
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Clark M, Diring S, Retailleau P, McMillin D, Ziessel R. Spectroscopic Properties of Orthometalated Platinum(II) Bipyridine Complexes Containing Various Ethynylaryl Groups. Chemistry 2008; 14:7168-79. [DOI: 10.1002/chem.200701975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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98
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Shao P, Li Y, Sun W. Platinum(II) 2,4-Di(2′-pyridyl)-6-(p-tolyl)-1,3,5-triazine Complexes: Synthesis and Photophysics. Organometallics 2008. [DOI: 10.1021/om701285c] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Pin Shao
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516
| | - Yunjing Li
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516
| | - Wenfang Sun
- Department of Chemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516
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99
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Tam AY, Lam W, Wong KC, Zhu N, Yam VW. Luminescent Alkynylplatinum(II) Complexes of 2,6-Bis(N-alkylbenzimidazol-2′-yl)pyridine-Type Ligands with Ready Tunability of the Nature of the Emissive States by Solvent and Electronic Property Modulation. Chemistry 2008; 14:4562-76. [DOI: 10.1002/chem.200701914] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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100
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Pritchett TM, Sun W, Guo F, Zhang B, Ferry MJ, Rogers-Haley JE, Shensky W, Mott AG. Excited-state absorption in a terpyridyl platinum(II) pentynyl complex. OPTICS LETTERS 2008; 33:1053-1055. [PMID: 18483509 DOI: 10.1364/ol.33.001053] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The singlet excited-state lifetime of a terpyridyl platinum(II) pentynyl complex was determined to be 268+/-87 ps by fitting femtosecond transient absorption data, the triplet excited-state lifetime was found to be 62 ns by fitting nanosecond transient absorption decay data, and the triplet quantum yield was measured to be 0.16. A ground-state absorption cross section of 2.5 x 10(-19) cm(2) at 532 nm was deduced from UV-vis absorption data. Excited-state absorption cross sections of 3.5 x 10(-17) cm(2) (singlet) and 4.5 x 10(-17) cm(2) (triplet) were obtained by using a five-level dynamic model to fit open-aperture Z scans at picosecond and nanosecond pulse widths and a variety of pulse energies.
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Affiliation(s)
- Timothy M Pritchett
- US Army Research Laboratory, AMSRD-ARL-SE-EM, 2800 Powder Mill Road, Adelphi, Maryland 20783-1197, USA.
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