• 한국전기화학회:학술대회논문집
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• 한국전기화학회 1998년도 제1회 총회 및 추계학술발표회
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• pp.31-31
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• 1998

• Environmental Engineering Research
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• 제8권2호
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• pp.59-71
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• 2003

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.108-108
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• 2011

Organometallic complexes containing unpaired spins, such as metalloporphyrin or metallophthalocyanine, have extensively studied with increasing interests of their promising model systems in spintronic applications. Additionally, the use of these complexes as an acceptor molecule in chemical sensors has recently received great attentions. In this presentation, we have investigated adsorption of nitric oxide (NO) molecules at Co-porphyrin molecules on Au(111) surfaces with scanning tunneling microscopy and spectroscopy at low temperature. At the location of Co atom in Co-porphyrin molecules, we could observe a Kondo resonance state near Fermi energy in density of states (DOS) before exposing NO molecules and the Kondo resonance state was disappeared after NO exposing because the electronic spin structure of Co-porphyrin were modified by forming a cobalt-NO bonding. Furthermore, we could locally control the chemical reaction of NO dissociations from NO-CoTPP by electron injections via STM probe. After dissociation of NO molecules, the Kondo resonance state was recovered in density of state. With a help of density functional theory (DFT) calculations, we could understand that the modified electronic structures for NO-Co-porphyrin could be occurred by metal-ligand hybridization and the dissociation mechanisms of NO can be explained in terms of the resonant tunneling process via molecular orbitals.

• 대한화학회지
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• 제36권4호
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• pp.558-564
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• 1992

여러 가지 치환기를 가지는 망간 포피린착물을 촉매로 사용하여 CH$_2$Cl$_2$ 용매하에서 styrene과 NaOCl간의 반응에 대한 수율을 구하였다. ortho 위치에 치환기를 가지는 망간 포피린 착물과 전자받게성의 치환기를 가지는 망간 포피린착물일 때 반응속도와 에폭사이드에 대한 선택성이 증가했다. 또한 망간 포피린착물에 축상 리간드로서 이미다졸을 도입할 때 반응속도와 에폭사이드에 대한 선택성이 증가했다. Michealis-Menten식을 이용한 반응속도론적 연구에 의하면 착물의 촉매능에 더 큰 영향을 주는 요소는 $K_m$ 임을 알았다. $K_m$ 값이 작을수록 더 큰 결합친화도를 가진다. 이론적인 연구로 EHMO계산에 의해 나온 결과와 실험에 의해 나온 결과는 좋은 일치를 보여주었다.

• 대한화학회지
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• 제39권5호
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• pp.364-370
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• 1995

비산화-환원 금속인 Ga(III), In(III), TI(III)을 포함하는 금속 포르피린을 촉매제로 NaOCl을 산화제로 하여 올레핀의 촉매적 산화반응을 $CH_2Cl_2$에서 연구하였다. 포르피린은 $(p-CH_3O)TPP,\;(p-CH_3)TPP,\;TPP,\;(p-F)TPP,\;(p-Cl)TPP $그리고 $(F_20)TPP$를 사용하였다. 올레핀은 $(p-CH_3O)-,\;(p-CH_3)-,\;(p-H)-,\;(p-F)-,\;(p-Cl)-,\;(p-Br)styrene$ 그리고 cyclopentene, cyclohexene을 사용하였다. 올레핀 산화반응에서 기질의 전환율(%)은 금속 포르피린 및 기질의 치환기 효과와 중심 금속이온 성질에 따라 고찰하였다. TPP 치환기에 따른 전환율의 변화는 $p-CH_3O$ < $p-CH_3$ < H < p-F < p-Cl 순서로 증가하였다. 이러한 증가는 TPP의 $4{\sigma}$값의 증가 순서와 일치하였다. 기질의 치환기에 따른 전환율의 변화는 $p-CH_3O$ > $p-CH_3$ > H > p-Cl > p-Br 순서로 치환기의 ${\sigma}^+$값이 증가할수록 오히려 감소하였다. 올레핀의 산화 반응에서 In(III)-, Tl(III)-포르피린은 Ga(III)-포르피린에 비하여 높은 촉매 활성을 나타내었다.

• Rapid Communication in Photoscience
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• 제3권3호
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• pp.59-60
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• 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.

• 대한화학회지
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• 제37권12호
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• pp.1080-1086
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• 1993

• 한국응용과학기술학회지
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• 제15권2호
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• pp.41-48
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• 1998

The catalytic oxidations of several cycloolefins in $CH_2Cl_2$ were been investigated using Mn(III)-, Fe(III)-porphyrin complexes as a catalyst and sodium hypochlorite as a terminal oxidant. Porphyrins were $(p-CH_3O)TTP,\;(p-CH_3)TTP,$ TPP, (p-F)TPP, (p-Cl)TPP and $(F_{20})TPP$ (TPP = tetraphenylporphyrin), and olefins were cyclopentene, cyclohexene and cycloheptene. The substrate conversion yield was discussed according to the substituent effects of metalloporphyrin. The conversion yield of substrate by changing the substituent of TPP increased in the order of $p-CH_3O$ < $p-CH_3$ < H < p-F < p-Cl, which was consistent with the sequence of $4{\sigma}$ values of TPP. The conversion of cycloalkene followed the order of $C_5\;<\;C_6\;<\;C_7$.

• 한국응용과학기술학회지
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• 제17권1호
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• pp.15-21
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• 2000

The catalytic hydroxylation of several cycloalkanes in dichloromethane have been investigated using In(Ⅲ)-, Tl(Ⅲ)-porphyrin complexes as a catalyst and NaClO, $NaClO_{2}$, $H_{2}O_{2}$ as a terminal oxidant. Porphyrins were TPP and ($F_{20}$)TPP (TPP = tetraphenylporphyrin) and substrates were cyclopentane, cyclohexane, cycloheptane and cyclooctane. The substrate conversion yield was discussed according to the substituent effect and hinderance effect of metalloporphyrin and the radius effect of non-redox metal ion. The conversion yield of cycloalkane followed the order of $ C_{5} $ < $ C_{6}$ < $ C_{7}$ = $ C_{8}$. In this experimental condition $NaClO_2$ was rather efficient terminal oxidant than NaClO and $H_{2}O_{2}$.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.35-38
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• 2012

Room temperature oxidation of organic sulfides with polyvinylpyrrolidone-supported hydrogen peroxide (PVP-$H_2O_2$) in the presence of Mn(III) complexes of meso-tetraphenylporphyrin, Mn(TPP)X (X = OCN, SCN, OAc, Cl) and imidazole (ImH) leads to the highly chemoselective (ca. 90%) oxidation of sulfides to the corresponding sulfoxide. The efficiency of reaction has been shown to be influenced by different reaction parameters such as the nature of counterion (X) and solvent as well as the molar ratio of reactants. Using Mn(TPP)OCN and ImH in 1:15 molar ratio and acetone as the solvent leads to the efficient oxidation of different sulfides.