• Title/Summary/Keyword: Porphyrins

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Facile Syntheses of Modified Tripyrranes and Their Application to the Syntheses fo Regioisomerically Pure Porphyrin Derivatives

  • 허필연;이창희
    • Bulletin of the Korean Chemical Society
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    • v.17 no.6
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    • pp.515-520
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    • 1996

  • Simple conditions were discovered to afford tripyrranes by reaction of 2,5-bis(α-hydroxymethyl)furan or 2,5-bis(α-hydroxy-α-phenylmethyl)thiophene with excess pyrrole in the presence of acid catalyst. Stepwise synthesis of porphyrins with core-ligand modification and synthesis of meso-tetraarylporphyrins bearing two different substituents in cis orientation have developed as building blocks for the various porphyrin-based model systems. Consequently, 21-thia-23-oxa-10,15-diphenylporphyrin (28), 21-oxa-10,15-diphenylporphyrin (29) and 21-oxa-23-carba-12-aza-10,15-diphenylporphyrin (30) were synthesized by acid-catalyzed [3+1] condensation between tripyrranes and 2,5-bis(α-hydroxymethyl)pyrrole or 2,5-bis(α-hydroxy-α-phenylmethyl)thiophene. The synthetic pathway described here gave regioisomerically pure porphyrins and thus overcame the synthetic problems associated with separation and purification of regioisomeric mixture.

  • https://doi.org/10.5012/bkcs.1996.17.6.515 인용 PDF

Surface Enhanced Raman Spectroscopic Studies on Zn(Ⅱ) and Mn(Ⅲ) Tetrakis (4-N-Methyl Pyridyl) Porphyrins

  • Song, Ok-Keun;Yoon, Min-Joong;Kim, Dong-Ho
    • Bulletin of the Korean Chemical Society
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    • v.11 no.4
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    • pp.286-290
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    • 1990

  • The surface enhanced Raman scatterings of Zn(Ⅱ) tetrakis (4-N-methyl pyridyl) porphyrins were studied in silver sol. Zn(Ⅱ) tetrakis (4-N-methyl pyridyl) porphyrin was found to be adsorbed on silver surface via flat-on geometry with some inhomogeneous distribution in the orientation of pyridyl groups. Both the selective enhancement of Raman modes depending on the mode character and the theoretical arguments of SERS are utilized to support the above conclusion. The surface induced substitution reaction of Mn(Ⅲ) tetrakis (4-N-methyl pyridyl) porphyrin chloride to Ag(Ⅱ) tetrakis (4-N-methyl pyridyl) porphyrin was detected via surface enhanced Raman spectrum.

  • https://doi.org/10.5012/bkcs.1990.11.4.286 인용 PDF

The Studies on Molecular Geometries and Electronic Structures of Substituted meso-Catecholic Porphyrins: DFT Methods and NSD

  • Park, Seung-Hyun;Kim, Su-Jin;Kim, Jin-Dong;Park, Sung-Bae;Huh, Do-Sung;Shim, Yong-Key;Choe, Sang-Joon
    • Bulletin of the Korean Chemical Society
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    • v.29 no.6
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    • pp.1141-1148
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    • 2008

  • Geometry optimizations and electronic structure calculations are reported for meso-tetraphenyl porphyrin (TPP) and a series of meso-substituted catecholic porphyrins (KP99150, KP99151, KP99152, KP99153, and KP99090) using density functional theory (DFT). The calculated B3LYP//RHF bond lengths are slightly longer than those of LSDA//RHF. The calculated electronic structures clearly show that TPP and meso-catecholic group contribute to π-electron conjugation along porphyrin ring for HOMO and LUMO, significantly reduced the HOMO-LUMO gap. The wavelength due to B3LYP energy gaps is favored with experimental value in Soret (B), and LSDA energy gaps are favored with experimental value in visible bands (Q). The electronic effect of the catecholic groups is to reduced energies of both the HOMOs and LUMOs. However, the distortion of porphyrin predominantly raises the energies of the HOMOs, so the net result is a large drop in HOMO and smaller drop in LUMO energies upon meso-substituted catecholic group of the porphyrin macrocycle as shown in KP99151 and KP99152 of Figure 5(a). These results are in reasonable agreement with normal-coordinate structural decomposition (NSD) results. The HOMO-LUMO gap is an important factor to consider in the development of photodynamic therapy (PDT).

  • https://doi.org/10.5012/bkcs.2008.29.6.1141 인용 PDF KSCI

Syntheses of Metalloporphyrins and Polymer-bonded Metalloporphyrin and Their Catalytic Effects on Benzoquinone Photoreduction (Metalloporphyrins 와 Polymer-bonded Metalloporphyrin 의 합성 및 Benzoquinone 광환원반응의 촉매효과)

  • Kyu-Ja Whang;Hee-Kyung Lee;Yong-Keun Lee
    • Journal of the Korean Chemical Society
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    • v.35 no.5
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    • pp.569-574
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    • 1991

  • Six free base porphyrins were synthesized by reacting pyrrole with benzaldehyde or its derivatives and then reacted with metal chlorides to prepare corresponding metal complexes. In addition, polymer-bonded porphyrins were synthesized by treating chloromethylated styrene-divinyl benzene (1%) copolymer beads with meso-tetra (p-aminophenyl)porphyrin (TNPP) solution and then treated with cupric chloride to obtain Cu(Res-NH-TPP-$NH_2$). The porphyrin compounds were characterized by visible, inffrared and electron spin resonance spectral analyses. The metal contents of metalloporphyrins were determined by atomic adsorption spectrophotometry. The synthesized porphyrin compounds were subsequently examined for their catalytic strength and found the activity to increase in the following order: free base porphyrins; metalloporphyrins; polymer-bonded metalloporphyrin. Among metalloporphyrins, Cu-TNPP showed the greatest catalytic power.

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