Selective oxidative synthesis of meso-beta fused porphyrin dimers

2013 ◽  
Vol 17 (04) ◽  
pp. 247-251 ◽  
Author(s):  
Bradley J. Brennan ◽  
Jaro Arero ◽  
Paul A. Liddell ◽  
Thomas A. Moore ◽  
Ana L. Moore ◽  
...  
Keyword(s):  
Electrochemical Properties ◽  
High Yield ◽  
Free Base ◽  
Bond Forming ◽  
Radical Coupling ◽  
Electrochemical Window ◽  
Nir Absorption ◽  
Efficient Route ◽  
Uv Visible ◽  
Porphyrin Dimers

An efficient route to meso-β doubly connected fused porphyrin dimers was developed. Synthesis of the dimers incorporated two successive C–C bond-forming steps selectively coupling unsubstituted meso- and β-positions. Using Cu(BF4)2 as an oxidant in nitromethane solvent, the radical coupling of Cu(II) -porphyrins occurred in high yield and without side-products, allowing chromatography-free purification. Efficient demetalation of the product yielded free-base derivatives and the possibility to incorporate other metals into the macrocycles. The absorption and electrochemical properties vary with the inserted metal, showing broad UV-visible-NIR absorption and multiple one-electron oxidations/reductions in a relatively narrow electrochemical window.

Facile synthesis, spectroscopic and electrochemical properties, and theoretical calculations of porphyrin dimers with a bridging amide-bonded xanthene moiety

2015 ◽  
Vol 19 (07) ◽  
pp. 819-829 ◽  
Author(s):  
Xu Liang ◽  
Li Xu ◽  
Minzhi Li ◽  
John Mack ◽  
Justin Stone ◽  
...  
Keyword(s):  
Electronic Structures ◽  
Magnetic Circular Dichroism ◽  
Theoretical Calculations ◽  
Free Base ◽  
Facile Synthesis ◽  
Visible Absorption ◽  
H Nmr ◽  
Uv Visible ◽  
Porphyrin Dimers ◽  
Porphyrin Dimer

A free base porphyrin dimer bridged by a flexible amide-bonded xanthene moiety and its binuclear zinc(II) complex zinc(II) complex were synthesized and characterized. Structural characterization by MS and 1 H NMR spectroscopy confirmed the bridged porphyrin dimer structure. The properties of the dimers were characterized by IR, UV-visible absorption, fluorescence and magnetic circular dichroism (MCD) spectroscopy, and electrochemistry studies. Theoretical calculations were carried out to analyze the electronic structures of porphyrin dimers with a bridging amide-bonded xanthene moiety.

Synthesis and Photophysical Properties of a Conformationally Flexible Mixed Porphyrin Star-Pentamer

2009 ◽  
Vol 62 (7) ◽  
pp. 692 ◽  
Author(s):  
Toby D. M. Bell ◽  
Sheshanath V. Bhosale ◽  
Kenneth P. Ghiggino ◽  
Steven J. Langford ◽  
Clint P. Woodward
Keyword(s):  
Energy Transfer ◽  
Photophysical Properties ◽  
Fluorescence Decay ◽  
High Yield ◽  
Free Base ◽  
Time Resolved ◽  
Zinc Porphyrin ◽  
Relative Contribution ◽  
Synthetic Strategy ◽  
Decay Times

The synthesis of a porphyrin star-pentamer bearing a free-base porphyrin core and four zinc(ii) metalloporphyrins, which are tethered by a conformationally flexible linker about the central porphyrin’s antipody, is described. The synthetic strategy is highlighted by the use of olefin cross metathesis to link the five chromophores together in a directed fashion in high yield. Photoexcitation into the Soret absorption band of the zinc porphyrin chromophores at 425 nm leads to a substantial enhancement of central free-base porphyrin fluorescence, indicating energy transfer from the photoexcited zinc porphyrin (outer periphery) to central free-base porphyrin. Time-resolved fluorescence decay profiles required three exponential decay components for satisfactory fitting. These are attributed to emission from the central free-base porphyrin and to two different rates of energy transfer from the zinc porphyrins to the free-base porphyrin. The faster of these decay components equates to an energy-transfer rate constant of 3.7 × 109 s–1 and an efficiency of 83%, whereas the other is essentially unquenched with respect to reported values for zinc porphyrin fluorescence decay times. The relative contribution of these two components to the initial fluorescence decay is ~3:2, similar to the 5:4 ratio of cis and trans geometric isomers present in the pentamer.

Free-base corroles: determination of deprotonation constants in non-aqueous media

2007 ◽  
Vol 11 (04) ◽  
pp. 269-276 ◽  
Author(s):  
Jing Shen ◽  
Zhongping Ou ◽  
Jianguo Shao ◽  
Michał Gałęzowski ◽  
Daniel T. Gryko ◽  
...  
Keyword(s):  
Equilibrium Constants ◽  
Aqueous Media ◽  
Free Base ◽  
Organic Base ◽  
Experimental Conditions ◽  
Spectral Changes ◽  
Base Analysis ◽  
Uv Visible ◽  
The Given

A series of free-base corroles with different electron-donating or electron-withdrawing substituents were reacted with piperidine, 4-aminopyridine, 2-methylimidazole, 2-aminopyridine or pyridine in PhCN and the UV-visible spectral changes monitored during conversion of ( Cor ) H 3 to [( Cor ) H 2]- as a function of the concentration and strength of the added organic base. Analysis of the UV-visible spectral changes as a function of the added base concentration enabled calculation of equilibrium constants ( logK ) for deprotonation of each corrole under the given experimental conditions. Relationships are examined between the experimentally measured logK values and previously published spectroscopic and structural properties of the compounds.

scholarly journals Dye-sensitized solar cell based on an inclusion complex of a cyclic porphyrin dimer bearing four 4-pyridyl groups and fullerene C60

RSC Advances ◽  
2016 ◽  
Vol 6 (20) ◽  
pp. 16150-16158 ◽  
Author(s):  
Yousuke Ooyama ◽  
Koji Uenaka ◽  
Takuya Kamimura ◽  
Shuwa Ozako ◽  
Masahiro Kanda ◽  
...  
Keyword(s):  
Solar Cell ◽  
Dye Sensitized Solar Cells ◽  
Fullerene C60 ◽  
Dye Sensitized Solar Cell ◽  
Free Base ◽  
New Class ◽  
Dye Sensitized ◽  
Sensitized Solar Cells ◽  
Porphyrin Dimers ◽  
Porphyrin Dimer

Cyclic free-base porphyrin dimers linked by butadiyne or phenothiazine bearing four 4-pyridyl groups and their inclusion complexes with fullerene C60 have been applied to dye-sensitized solar cells as a new class of porphyrin dye sensitizers.

Superexchange mediated energy transfer in zinc(ii) porphyrin–free base porphyrin dimers: comparison of m- and p-bis(phenylethynyl) phenylene linked dimers

2011 ◽  
Vol 13 (28) ◽  
pp. 12712 ◽  
Author(s):  
Motoko S. Asano ◽  
Ken-ichi Yamashita ◽  
Masato Kitabayashi ◽  
Kazuki Kusama ◽  
Daichi Kagota ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Free Base ◽  
Porphyrin Dimers

scholarly journals Chiral Amphiphilic Secondary Amine-Porphyrin Hybrids for Aqueous Organocatalysis

Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3420 ◽  
Author(s):  
Aitor Arlegui ◽  
Pol Torres ◽  
Victor Cuesta ◽  
Joaquim Crusats ◽  
Albert Moyano
Keyword(s):  
Catalytic Activity ◽  
High Yield ◽  
Aldol Reactions ◽  
Free Base ◽  
Reaction Products ◽  
Chirality Transfer ◽  
Base Form ◽  
Low Degree ◽  
Acidic Conditions ◽  
Ph Dependent

Two chiral proline-derived amphiphilic 5-substituted-10,15,20-tris(4-sulfonatophenyl)porphyrins were prepared, and their pH-dependent supramolecular behavior was studied. In neutral aqueous solutions, the free-base form of the hybrids is highly soluble, allowing enamine-based organocatalysis to take place, whereas under acidic conditions, the porphyrinic protonated core of the hybrid leads to the formation of self-assembled structures, so that the hybrids flocculate and their catalytic activity is fully suppressed. The low degree of chirality transfer observed for aqueous Michael and aldol reactions strongly suggests that these reactions take place under true “in water” organocatalytic conditions. The highly insoluble catalyst aggregates can easily be separated from the reaction products by centrifugation of the acidic reaction mixtures, and after neutralization and desalting, the sodium salts of the sulfonated amine-porphyrin hybrids, retaining their full catalytic activity, can be recovered in high yield.

meso-Aryl substituted free-base tripyrrins: preparation and electrochemically induced protonation/deprotonation reactions. Single crystal X-ray analysis of (2,6-diFPh)2TriPyH

RSC Advances ◽  
2015 ◽  
Vol 5 (117) ◽  
pp. 96769-96776 ◽  
Author(s):  
Ru Feng ◽  
Zhongping Ou ◽  
Zhaoli Xue ◽  
Yuanyuan Fang ◽  
Yang Song ◽  
...  
Keyword(s):  
Single Crystal ◽  
Electrochemical Properties ◽  
Free Base ◽  
Nonaqueous Media ◽  
X Ray

Three meso-substituted free-base tripyrrins were successfully isolated as side-products from the synthesis of triarylcorroles and characterized as to their electrochemical properties in nonaqueous media.

Controllable Synthesis of Functional Polyaniline Nanotubes via a Complex Template

2015 ◽  
Vol 1120-1121 ◽  
pp. 220-224
Author(s):  
Ying Wang ◽  
Dong Hao Sun ◽  
Yan Feng Guo
Keyword(s):  
Electric Conductivity ◽  
Room Temperature ◽  
In Situ Polymerization ◽  
High Yield ◽  
Controllable Synthesis ◽  
Order Of Magnitude ◽  
Uv Visible ◽  
Acid Orange Ii ◽  
High Electric Conductivity

Functional Polyaniline (PANI) nanotubes are easily synthesized in high yield by an in situ polymerization using a fibrillar complex of acid orange II (AO II) and FeCl3as a template. During the process, the complex templates help direct the growth of fibrillar PANI on their surfaces, resulting in the formation of composite micro/nanofibers of PANI. After polymerization, by the post-treatment of removing templates in 1.0 M hydrochloric acid solution, PANI nanotubes with azo function and high electric conductivity of PANI are readily fabricated. The PANI nanotubes have about 150nm-300nm in diameter and several microns in length. At room temperature, the electric conductivity of PANI nanotubes is up to 10-1S/cm order of magnitude. The characterizations, including FTIR, UV-visible, XRD and TG, are presented.

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