- Synthesis and Study of a Mixed-ligand Ruthenium(II) Complex in Its Ground and Excited States: Bis(2,2'-bipyridine)(dipyridophenazine-N4N5)ruthenium(II)
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The ruthenium(II) complex 2+ (bipy = 2,2'-bipyridine, dppz = dipyridophenazine) was synthesized, characterized, and studied.Its oxidation and first reduction potentials are respectively 1.24 and -1.02 V (vs. saturated calomel electrode).The maxima of the metal-to-ligand charge-transfer absorption and emission occur respectively at 448 and 610 nm.These data suggest that 2+ is made up of two electronically independent units, one behaving as a 2+-like chromophore, the other as a phenazine-like electron acceptor.Excited-state absorption spectra were obtained for 2+ and its parent complex 2+.Above 500 nm the latter shows only one maximum (at 510 nm), and the former shows two maxima (around 526 and 557 nm), whereas radical anions of both bipyridine and phenazine or dipyridophenazine show two maxima (at 512 and 552 nm for phenazine).In the case of 2+ these results can be interpreted in terms of a light-induced directed charge transfer from the ruthenium to the phenazine part of the dipyridophenazine ligand, and its localization on this ligand moiety.Photochemical properties of 2+ were studied in ethanol.The excited state of the complex is quenched both by an electron acceptor (methylviologen, kq = 1.37*109 dm3 mol-1 s-1) and an electron donor (triethanolamine, kq = 4.40*107 dm3 mol-1 s-1).
- Amouyal, Edmond,Homsi, Abdulrazzak,Chambron, Jean-Claude,Sauvage, Jean-Pierre
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- Eu-MOFs with 2-(4-carboxyphenyl)imidazo[4,5-f]-1,10-phenanthrolineand ditopic carboxylates as coligands: Synthesis, structure, high thermostability, and luminescence properties
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(Graph Presented) Hydrothermal reactions of europium(III) salt with 2-(4-carboxyphenyl)imidazo[4,5- f ]-1,10-phenanthroline and dicarboxylic acid as coligands - benzene-1,4-dicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 2,5-dibromoterephthalic acid, and naphthalene-1,4-dicarboxylic acid - lead to four europium fluorescent materials (1-4). Structural analyses reveal that 1 - 4 have binuclear 3D metal - organic frameworks with different channels, void volumes, and conjugated structures tuned by ditopic carboxylates. There are no latticed and coordinated water molecules occurring in 1 - 3, while the free water molecules fill in 1D channels of 4. 4′ was readily obtained via water removal of 4. Thermal analyses of all compounds show the high thermal stability of the main framework up to 450 °C. Optical studies indicate that 1 - 4 and 4′ show the characteristic red luminescence emission of the EuIII ion in the visible regions at room temperature. On the basis of emission spectra, their luminescence lifetimes were determined. In particular, compound 4??? shows a longer lifetime (τ = 0.942 ms) and significantly enhanced quantum yield (39%) compared with those of 1 (11%, 0.770 ms), 2 (4%, 0.414 ms), 3 (18%, 0.807 ms), and 4 (26%, 0.858 ms).
- Zhang, Sheng,Yang, Yang,Xia, Zheng-Qiang,Liu, Xiang-Yu,Yang, Qi,Wei, Qing,Xie, Gang,Chen, San-Ping,Gao, Sheng-Li
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- Solvent effect on the reactivity of 1,10-phenanthroline-5,6-dione towards diazomethane
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In an aprotic medium, such as THF, Et2O or CH2Cl2, the reaction of 1,10-phenanthroline-5,6-dione with diazomethane gave 5,6-methylenedioxy-1,10-phenanthroline as the only product. In contrast, in a protic solvent, such as 2-propanol or ethanol, the nucleophilic attack of CH2N2 occurred on carbonyl carbons, resulting in the formation of dispiro[5,6-dihydro-1,10-phenanthroline-5,6-dioxirane] as the main product. When the reaction with CH2N2 was carried out in methanol, the only product which could be isolated from the reaction mixture, dimethyl 2,2′-bipyridine-3,3′-dicarboxylate, resulted from a break of the C(5)-C(6) bridge.
- Antkowiak,Sobczak
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- Hydrothermal syntheses, crystal structures, and photophysical properties of two coordination polymers with mixed ligands
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Two novel metal-organic coordination polymers [Cd(ipdt)(m-BDC)·3H2O]n (1) and [Pb(mip)2(NTC) ·2H2O]n (2) [ipdt = 2,6-Dimethoxy-4-(1H-1,3,7,8-tetraaza-cyclopenta[l]phenanthren-2-yl)-phenol, mip = 2-(3-
- Yan, Li,Liu, Chun-Ling
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- 2'-pyrazol-1H-imidazole [4,5-f][1,10] phenanthroline derivate and preparing method and application thereof
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The invention relates to a 2'-pyrazol-1H-imidazole [4,5-f][1,10] phenanthroline derivate and a preparing method and application thereof. According to the 2'-pyrazol-1H-imidazole[4,5-f][1,10] phenanthroline derivate, different substituted acetophenone and semicarbazlde hydrochloride and 2,4-dinitrobenzene serve as raw materials, the target compound, namely the 2'-pyrazol-1H-imidazole [4,5-f][1,10] phenanthroline derivate is obtained through a five-step reaction, and the obtained target compound is used for applied research of cell line growth inhibition and apoptosis activity for resisting three kinds of cancer cells including the non-small cell lung cancer cell lines A549, human liver cancer cell lines HepG2 and human breast carcinoma cell lines MCF-5. Most compounds can make the experiment cancer cells restrained and apoptotic, high effects are generated on the A549 and HepG2 cell lines are achieved particularly, and selective toxicity on the A549 cell lines is generated particularly. According to the 2'-pyrazol-1H-imidazole [4,5-f][1,10] phenanthroline derivate, a large reference value is provided for finding new anti-tumor micromolecular medicines and is particularly provided for promoting clinical medicine research and development of the phenanthroline derivate.
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Paragraph 0046; 0050
(2017/05/19)
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- Detection of biomolecules by sensitizer-linked substrates
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Methods and compositions for detecting and characterizing target biomolecules using sensitizer-linked substrate molecules are disclosed. High throughput screening assays and therapeutic applications of the inventions are also included.
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- Low quantum yields of relaxed electron transfer products of moderately coupled ruthenium(II)-cobalt(III) compounds on the subpicosecond laser excitation
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Photoinduced electron-transfer reactions of [(tpy)RuII(tpy-tpy) CoIII(tpy)]5+ (tpy = 2,2′:6′,2″-terpyridine and tpy-tpy = 6′,6″-bis(2-pyridyl)-2,2′:4′,4″: 2″,2″′-quarterpyridyne), [(tpy)RuII(tpy-ph-tpy) CoIII(tpy)]5+ (tpy-ptitpy = 1,4-bis[2,2′:6′,2″- terpyridine-4′-yl]benzene), and [(bpy)2RuII(tpphz) CoIII(bpy)2]5+ (bpy = 2,2′-bipyridine, and tpphz = tetrapyrido[3,2-a:2′,3′-c:3″,2″-h:: 2″′,3″′-j]phenazine) were studied in the range 140-298 K by means of subpicosecond transient absorption spectroscopy. 3MLCT(Ru) of [(tpy)RuII(L-L)CoIII(tpy)] 5+ (L-L: tpy-tpy and tpy-ph-tpy) underwent intramolecular electron-transfer (EET) reaction to form [2RuIII(tpy)(L-L) 2CoII(tpy)]5+ in a shorter time than 10 ps. Low quantum yields of the EET products (0.53 for tpy-tpy and 0.41 for tpy-ph-tpy in butyronitrile at 298 K) measured before the fast return electron-transfer were found as in the intermolecular electron-transfer quenching of 3MLCT(Ru) by [Co(tpy)2]3+. The quantum yield of [(tpy)-RuIII(tpy-tpy)CoII(tpy)]5+ (Φ) decreases to 0.38 in a slowly reorganizing solvent of propylene carbonate and that of [(tpy)RuII(tpy-ph-tpy)CoIII(tpy)]5+ to 0.21 at 180 K. The reductions in the EET yields, 1 - Φ, can be ascribed to a fast transition of the nonrelaxed EET product to the lowest triplet d-d* state of [CoIII(tpy)2] moiety during the solvent reorganization. A tunneling transition of the nonrelaxed EET products to the lowest lying d-d excited-state of [CoIII(tpy)2] moiety takes place as a hole transfer, HT, from the dπ-orbital of Ru(III) to that of Co(II) with a configuration of dπ6da*. An electronic coupling of dπ(Ru)-dπ(Co) estimated from the intensity of inter-valence transition of [(tpy)RuIII(L-L)RuII(tpy)]5+ (Collin, J.-P.; Laine, P.; Launay, J.-P.; Sauvage, J.-P.; Sour, A. J. Chem. Soc., Chem. Commun. 1993, 434) is large enough to carry out the HT. The weak coupling of dπ(Ru)-dπ(Co) in the case of [(bpy)2Ru(tpphz) Co(bpy)2]5+ attenuates the HT rate to bring about a high yield of EET (0.8). The possibility that energy-transfer of 3MLCT(Ru) to the Co(III) moiety via an intermediate super-exchange coupling between dπ(Ru) and dπ(Co) occurs in competition with the EET of [(tpy)Ru III(tpy-ph-tpy)CoII(tpy)]5+ is also pursued.
- Torieda, Hiroaki,Nozaki, Koichi,Yoshimura, Akio,Ohno, Takeshi
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p. 4819 - 4829
(2007/10/03)
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- On the chlorine addition to the C(5)-C(6) bridge and the N-oxidation of 1,10-phenanthroline
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It was found that under the influence of aqueous hypochlorite 1,10-phenanthroline (1) is initially transformed into 5,6-dichloro-5,6-dihydro-1,10-phenanthroline (2) and 5-chloro-6-hydroxy-5,6-dihydro-1,10-phenanthroline (8). The latter readily undergoes subsequent transformations either into a mixture of 5,5-dichloro-6-oxo-5,6-dihydro-1,10-phenanthroline (4) and 5,6-dioxo-5,6-dihydro-1,10-phenanthroline (5) or into the known 5,6-epoxy-1,10-phenanthroline (3) depending on the acidic or alkaline conditions, respectively. In contrast to the flat molecule of the starting 1, that of the dichloro derivative (2) being twisted at the central bond of the bipyridine system can be easily N-oxidized to di-N-oxide (11). Both 2 and its di-N-oxide (11) in the presence of sodium isopropoxide at 0°C freely lost hydrogen chloride and returned to the fully aromatic system of 5-chloro-1,10-phenanthroline (9) and its di-N-oxide (13), respectively.
- Antkowiak, Roza,Antkowiak, Wieslaw Z.
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p. 893 - 909
(2007/10/03)
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- The synthesis of ascididemin
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A short synthsis of the pentacyclic marine alkaloid ascididemin 1 (four steps, 21% yield) from 1,10-phenanthroline 16 is described. The key step, photocyclisation of the quinoneimine 14 in sulphuric acid, is the first such aza stilbene photocyclisation of a quinoneimine. Intermediate 14 is prepared in a single, but low yielding, step from the quinone 4 in an aza Wadsworth-Emmons reaction, or in much better yield from the epoxide 17 by treatment with 2- iodoaniline and triethylaluminium, followed by oxidation with barium manganate.
- Moody, Christopher J.,Rees, Charles W.,Thomas, Robert
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p. 3589 - 3602
(2007/10/02)
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- Electron Transfer and Ion Pairing, 27. Preparation of Semiquinone Ion Pairs by Reduction of Quinones Using Tetraalkylammonium Boranate in Aprotic Salt Solutions: 1,10-Phenanthrolin-5,6-dione
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Ion pairs of 1,10-phenanthrolin-5,6-dione radical anion -Me+n>*+(n-1) with Me+n = Mg2+, Ca2+, Sr2+, Zn2+, Cd2+, Pb2+ and La3+ are advantageously prepared in aprotic DMF solution containing appropriate metal salts Me+nX- by using the "mild" single-electron reducing agent tetra(n-butyl)ammonium-boranate R4N+BH4-.For comparison, the "nacked" radical anion with the largely interaction-free + counter cation is chosen, which is formed on reduction with potassium in THF solution of (2.2.2)-cryptand.Addition of excess Na+- to the reduction solution only yields a solvent-separated ion pair M*-)DMF...(Na+)DMF, whereas in the presence of multiply charged counter cations Me+n the respective contact ion pair radical cations -Me+n>*+(n-1) are formed.Their g values decrease with increasing nuclear charge of Me+n and their metal-s-spin densities increase with the effective counter cation charge n+/rMe+n.The ESR/ENDOR data recorded suggest Me+n complexation by the δ-OC-COδ- chelate tongs and the ion pair stability, which is modified by the dielectric properties of the solvent used, may be rationalized by the Coulombic attraction between the radical anion M*- and the counter cations Me+n.Keywords: 1,10-Phenanthrolin-5,6-dione, Reduction by R4N+BH4-, Contact Ion Pairs, ESR/ENDOR Spectra
- Bock, H.,Haenel, P.
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p. 288 - 300
(2007/10/02)
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