- Through the challenging synthesis of tetraphenylporphyrin derivatives bearing nitroxide moieties
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Tetraphenylporphyrin derivatives a synthetic heterocycles with convenient preparation and a richness of properties which make them attractive in broad fields such as energy, life and materials sciences. Thus, in the quest for new radical architectures, tetraphenylporphyrins are prime candidates. To this end, we designed free-base tetraphenylporphyrins bearing nitronyl and imino nitroxide moieties covalently bonded to the para-position of the meso-phenyl substituent. Their detailed synthesis and characterization are reported here.
- ?nal, Emel,Fidan, Ismail,Luneau, Dominique,Hirel, Catherine
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- Enhancing triplet sensitization ability of donor-acceptor dyads: Via intramolecular triplet energy transfer
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Two covalently linked porphyrin palladium (PdPor)-9,10-diphenylanthracene (DPA) donor-acceptor (D-A) systems, connected through the 2-position (PdPor-2-DPA) or 9-position (PdPor-9-DPA) of DPA, are prepared as sensitizers of triplet-triplet annihilation upconversion (TTA-UC). The steady-state absorption spectra demonstrate that PdPor and DPA in these compounds are electronically independent in the ground state. Phosphorescence spectra and femtosecond transient absorption spectra reveal that ultrafast intramolecular triplet energy transfer (iTET) from the PdPor unit to the DPA unit can be conducted in PdPor-9-DPA but not in PdPor-2-DPA. This may be caused by the stronger electronic coupling between PdTPP and DPA in PdPor-9-DPA that is essential for Dexter type triplet energy transfer. In addition, these two dyads are used as a triplet energy donor in TTA-UC for sensitizing DPA. The maximum upconversion efficiency for PdPor-9-DPA is about 23.59%, which is much larger than that of PdPor-2-DPA (10.48%). These results confirm that the iTET efficiency would affect the upconversion efficiency when the D-A system is adopted as a triplet donor. This provides new insights into designing D-A systems with highly efficient iTET as candidates for triplet energy donors in TTA-UC.
- Li, Xiyou,Liu, Heyuan,Liu, Shanshan,Shen, Li,Wang, Xiangyang,Zhao, Dezhi
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- SYNTHESIS AND PHOTOPHYSICS OF DIAZA-CROWN ETHER-BASED BISPORPHYRINS
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The bisporphyrin N,N'-bis-4,13-diaza-18-crown-6 and its mono- and dizinc derivatives were synthesized in 66percent, 46percent and 53percent yields, respectively, from 5-(4'-bromomethylphenyl)-10,15,20-triphenylporphyrin or its zinc derivative and 4,13-diaza-18-crown-6.The zinc-containing bisporphyrins form dimers in solution at low temperature or at high concentration.The unsymmetrical bisporphyrin; monozinc N,N'-bis-4,13-diaza-18-crown-6 shows singlet-singlet energy transfer from the zinc porphyrin moiety to the free base moiety in both the monomeric and the dimeric form.The energy transfer rates were determined using time-resolved fluorescence spectroscopy and were found to be 1.26x109 and 2.29x109 s-1 for the monomeric and dimeric form, respectively.The difference in energy transfer rates between the two forms can be rationalized by the difference in overlap between the donor fluorescence spectrum and acceptor absorption spectrum, donor-acceptor distance and donor-acceptor orientation.
- Martensson, Jerker,Sandros, Kjell,Wennerstroem, Olof
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- Metal-crown ether-porphyrin decorated gold nanoparticles as high sensitive raman ion probe
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A kind of gold nanoparticles modified with metal crown ether porphyrin (GNPs-CP) was synthesized and characterized. The surface of the resulting gold particles was partially covered by metal crown ether porphyrin molecules through strong covalent Au-S bon
- Li, Sen,Geng, Xin,Sun, Wen-Quan,Han, Guo-Zhi
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- Combining metalloporphyrins and cyclometalated complexes – A luminous pair?
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Cyclometalation is investigated as a method to modulate the photophysical properties of phosphorescent (benzo)porphyrins. For cyclometalation with Pt(II), 2-pyridyl groups were incorporated into three Pd(II) porphyrin complexes. Integration of the freely rotating cyclometalated 2-phenylpyridyl based motif in meso-position does not lead to notable spectral changes and only affects the luminescence decay time (about 2-fold decrease) in solution at room temperature. The decay times, however, are not affected in frozen glass at 77 K or immobilized into a rigid polystyrene matrix. In contrast, cyclometalation involving a 2-pyridyl unit in meso-position and the β-H of the porphyrin results in a large bathochromic shift (~ 1900 cm?1) of Q-bands in the absorption spectrum and the phosphorescence peak. A drastic decrease of the phosphorescence lifetime (about 20-fold) also is observed. Cyclometalation is accompanied by an increase of the singlet oxygen quantum yield to 85 % making the new dye a powerful red-light excitable 1O2 photosensitizer.
- Borisov, Sergey M.,Moritz, Yvonne,Steinegger, Andreas
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- Structure-Photoproperties Relationship Investigation of the Singlet Oxygen Formation in Porphyrin-Fullerene Dyads
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A systematic structure-photoproperties relationship study of the interactions of porphyrin-fullerene dyads with molecular oxygen was conducted on a set of three porphyrin-fullerene dyads, as this approach of related applications - oxygen sensitivity and photo-induced singlet oxygen generation - of such dyads remained to be endeavoured. To promote energy transfers between the porphyrin and fullerene units and limit undesired charge separation, a particular attention was devoted to the choice of the solvents for the photoproperties determination. Toluene, in which in addition the compounds investigated are not aggregated, was selected accordingly. The molecular orbital levels and energy gaps of the dyads were determined by electrochemistry and theoretical calculations. Their ground state absorption, steady-state fluorescence-based oxygen sensitivity and photo-induced singlet oxygen generation were determined. The dyads were designed to benefit from a facilitated synthetic porphyrin-fullerene coupling thanks to an easy access to formyl-functionalized porphyrins. The effect of two structural parameters was investigated: the presence of electron-donating hexyloxy chains at the para position of the meso-phenyl, and the presence of a phenylacetylene spacer. This latest factor appeared to have the most predominant effect on all these properties.
- ?nal, Emel,Topal, Sevinc Zehra,Fidan, Ismail,Berber, Sava?,Dumoulin, Fabienne,Hirel, Catherine
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- Synthesis and photodynamic activities of a new metronidazole-appended porphyrin and its Zn(II) complex
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One novel porphyrin 5,10,15-tris(phenyl)-20-[4-(2-(2-methyl-5-nitro-imidazolyl)ethoxyl)phenyl] porphyrin and its zinc(II) metalloporphyrin were synthesized and characterized by IR, UV-vis, 1H NMR, MS and elemental analysis. The single crystal s
- Yu, Qiong,Xu, Wei-Xia,Yao, Ya-Hong,Zhang, Zeng-Qi,Sun, Shu,Li, Jun
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- Bifunctional metal-free photo-organocatalysts for enantioselective aerobic oxidation of β-dicarbonyl compounds
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A series of bifunctional metal-free photo-organocatalysts have been developed by grafting the photosensitizer to cinchona-derived phase-transfer catalysts. Using air as a green oxidant and visible light as the driving force, these catalysts are applied to the oxidation of a range of β-dicarbonyl compounds in good yields (up to 97%) and enantioselectivities (up to 93:7 er).
- Tang, Xiao-fei,Feng, Shi-hao,Wang, Ya-kun,Yang, Fan,Zheng, Ze-hao,Zhao, Jing-nan,Wu, Yu-feng,Yin, Hang,Liu, Guang-zhi,Meng, Qing-wei
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- Preparation and application of double-porphyrin-containing compound
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The invention relates to a double-porphyrin compound with switching performance. The structural general formula of the double-porphyrin compound is I. The double-porphyrin compound provided by the invention not only can be complexed with fullerene supramo
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Paragraph 0029-0034
(2021/06/26)
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- Synthesis and reactivity of allenylporphyrins
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Several different methods have been utilized for the effective synthesis of a new class of porphyrins that contains the synthetically intriguing propadienyl (or allenyl) functional group. Of these approaches, successive Horner-Wadsworth-Emmons couplings p
- Plunkett, Shane,Dahms, Katja,Senge, Mathias O.
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p. 1566 - 1579
(2013/04/23)
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- SYNTHESIS OF TETRAPHENYLPORPHINES WITH ACTIVE GROUPS IN THE PHENYL RINGS6. SYNTHESIS OF MONOSUBSTITUTED TETRAPHENYLPORPHINES BY DIAZOTIZATION
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Monoaminophenyltriphenylporphines are diazotized and then used to produce monohalosubstituted tetraphenylporphines.Isomeric mono(p-hydroxyphenylazo)phenyltriphenylporphines are synthesized by replacing the azo group of diazonium salts of monosubstituted porphines with phenol.
- Syrbu, S. A.,Semeikin, A. S.,Berezin, B. D.
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p. 1255 - 1257
(2007/10/02)
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