• Rapid Communication in Photoscience
• /
• v.2 no.2
• /
• pp.39-41
• /
• 2013

It is interesting to introduce viologen moiety into photoactive compounds such as porphyrin and anthracene in the study of supramolecular system such as pseudorotaxanes. For the construction of photoactive pseudorotaxane based on porphyrin-viologen-anthracene triad or its zinc derivative threaded with bis-p-phenylene-34-crown-10 macrocycle, porphyrin-viologen-anthracene triad 1 and its zinc derivative zinc porphyrin-viologen-anthracene triad 2 were prepared and their absorption and fluorescence spectral properties were measured.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.2
• /
• pp.167-172
• /
• 2003

Alkyliron(Ⅲ) porphyrins, n-butyliron(Ⅲ) tetraphenylporphyrin, (TPP)Fe-Bu and n-butyliron(Ⅲ) tetrakis-(pentafluorophenyl)porphyrin, $(F_{20}TPP)Fe-Bu$ have been evaluated as suitable for olefin free-radical polymerization. Butyl radicals dissociated from n-butyliron(Ⅲ) porphyrin initiated the polymerization reaction, but the ratio of the propagation was low. The GCMS analysis of the reaction mixture of nbutyliron(Ⅲ) porphyrin and styrene has revealed several products containing two butyl groups, while traces of b-hydrogen-abstracted products were observed. The crystal structure of (TPP)Fe-Bu has been determined. The structure of the n-butyliron(Ⅲ) porphyrin reveals the compound containing five-coordinated iron with the average Fe-N distance of 1.973(1) Å and Fe-C of 2.030(2) Å. The iron atom is displaced by 0.137Å from a four nitrogen mean plane. Crystal system is triclinic, and space group is P-1.

• Journal of the Korean Chemical Society
• /
• v.55 no.3
• /
• pp.335-340
• /
• 2011

The solution properties of sodium n-dodecyl sulfate, as an anionic surfactant in the presence of a cationic watersoluble 5, 10, 15, 20-tetrakis (N-methylpyridinium-4-yl) porphyrin (TMPyP) has been comprehensively studied by means of conductometry, UV-vis and resonance light scattering (RLS) spectroscopies. The results represent the decreasing of critical micelle concentration of SDS solution due to increasing of TMPyP concentration. The stabilization of SDS micelle is due to neutralization of negative charge at the micelle surface. The presence of three different species of TMPyP in SDS solution has been unequivocally demonstrated: free porphyrin monomers, porphyrin monomers or aggregates bound to the micelles, and nonmicellar porphyrin/surfactant aggregates. Our results show SDS induced an aggregation in TMPyP. In fact two kinds of J-aggregations were observed: one of them for porphyrin monomers or aggregates bound to the micelles and the other for nonmicellar porphyrin/surfactant aggregates. However, the results represent the electrostatic interaction of TMPyP with SDS anion below the cmc.

• Journal of Hydrogen and New Energy
• /
• v.2 no.1
• /
• pp.7-13
• /
• 1990

We are interested in studying the artificial photolysis of water which mimics the natural plant photosynthesis. In the artificial system there should be a proper photosensitizer, electron donor and electron acceptor. Since Mn-tetramer is known to be the essential part for the oxygten-evolving system in the natural photosynthesis, it is important to know or study the reactivity of Mn-porphyrins. As a model for the Mn-tetramer in the natural photosynthesis, we prepared the lipophilic and hydrophilic Mn-porphyrins. For the lipophilic porphyrin with long hydrocarbon chain, the long hydrocarbon chain was inserted in the porphyrin ring formation step. For the hydrophilic porphyrin, the porphyrin was sulfonated with sulfuric acid. These syntheses of lipophilic and hydrophilic Mn-porphyrins are significant, since the behaviors of these compounds will be different in the microemulsions or vesicles. We also found that the Mn-porphyrins were photoreduced in the microemulsion and water in the presence of amines.

• Rapid Communication in Photoscience
• /
• v.3 no.3
• /
• pp.59-60
• /
• 2014

The trans-$A_2B_2$ porphyrin and Ni-porphyrin derivatives were synthesized by Suzuki coupling of bromoporphyrin with arylborate as a key step. The band gaps of those complexes were measured from their absorption, emission and cyclic voltammetric data. All the LUMO energy level of porphyrin derivatives is lower than that of P3HT, and the HOMO energy level is evaluated higher than the HOMO of PCBM.

• Rapid Communication in Photoscience
• /
• v.3 no.3
• /
• pp.50-52
• /
• 2014

Rotaxanes have been prepared using benzene-linked bis-porphyrin or bis-zinc porphyrin as a string component and bis-viologen as a macrocyclic ring component. Absorption and fluorescence spectra of rotaxane formed by complexation of two components have been investigated.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.3
• /
• pp.639-644
• /
• 2010

Amphiphilic porphyrin derivatives have been synthesized and characterized by $^1H$ NMR and MALDI-TOF-MS. All porphyrin derivatives showed very high solubility to aqueous medium as well as hydrophobic organic solvent. The UV-vis absorption of the porphyrin derivatives showed significant broadness and decrease of maximum intensity of absorption in aqueous solution. SEM experiment showed the formation of spherical micellar structure. The $T_1$ relaxation time of aqueous medium was drastically decreased in the presence of Mn(III)-porphyrin derivative, indicating that the supramolecular micelle has strong possibility to use as a $T_1$ contrast agent.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.2
• /
• pp.271-276
• /
• 2002

The energy relaxation dynamics of the lowest excited singlet and triplet states of the Zn(II)porphyrin monomer and its directly linked arrays were comparatively investigated with increasing the number of porphyrin moieties. While the fluorescence decay rates and quantum yields of the porphyrin arrays increased with the increase of porphyrin units, their triplet-triplet (T-T) absorption spectra and decay times remained almost the same. The difference in the trends of energy relaxation dynamics between the excited singlet and triplet states has been discussed in view of the electronic orbital configurations.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.9
• /
• pp.3411-3420
• /
• 2011

Kinetic and structural studies have been carried out on the effects of meso-tetrakis(4-sulfonatophenyl)-porphyrin ($H_2TPPS_4$) as an anionic and meso-tetrakis(3-N-methyl-pyridyl)porphyrin ($H_2TMPYP$) as a cationic porphyrin with adenosine deaminase (ADA) in 25 mM citrate/phosphate buffer, pH = 4-8, at $37^{\circ}C$ using UVvis spectrophotometry, circular dichroism (CD), fluorescence spectrophotometry as well as molecular dynamics (MD) and molecular docking. Kinetic results showed that the two porphyrins are non-competitive inhibitors. Increasing pH, increases $K_I$ and cationic porphyrin has a higher $K_I$ and lower binding constant ($K_b$) at all pH ranges. Analyzing the secondary structure revealed that both ligands decrease the secondary structure and that the anionic porphyrin is more effective.

• Journal of Photoscience
• /
• v.9 no.1
• /
• pp.9-12
• /
• 2002

A porphyrin derivative covalently tinted to Ni aria-macrocycle complex has been prepared. Absorption spectrum of porphyrin-Ni aria-macrocycle dyad (λ$\^$max/$\sub$a/=227 nm) was observed to similar to a sum of those of tetratolylporphyrin (λ$\^$max/$\sub$a/=419 nm) and Ni aza-macrocycle (λ$\^$max/$\sub$a/=227 nm), indicating no electronic interaction between porphyrin and Ni aza-macrocycle moieties. Fluorescence quantum yield of dyad (${\Phi}$$\sub$f/= 0.10) was same to that of tetratolylporphyrin (${\Phi}$$\sub$f/= 0.10). Photoinduced intramolecular electron transfer or energy transfer from excited porphyrin moiety to Ni(II) aza-macrocycle moiety should be very inefficient in dyad.