• Bulletin of the Korean Chemical Society
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• 제8권5호
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• pp.393-398
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• 1987

Solvolyses of 2-phenylethyl benzenesulfonates have been studied in methanol-water mixtures. Cross interaction constants, $\rho_{YZ}$, between substituents Y in the substrate and Z in the leaving group indicated somewhat closer distance between the two substituents than expected for the reaction system, which supported the involvment of phenyl group assisted pathway in the solvolysis. A smaller magnitude of $\rho_{YZ}$for MeOH was interpreted as the enhencement of solvent assisted pathway since MeOH is more nucleophilic than $H_2O$. Other selectivity parameters, Winstein coefficient m, Hammett's $\rho_Y^{+_Y}$ and $\rho_Z$, as well as activation parameters supported the participation of aryl assisted and aryl unassisted pathways in the $S_{N^2}$ process of the solvolysis reaction.

• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.2105-2110
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• 2013

Carbon-fiber-supported NiO catalytic filters for oxidation of volatile organic compounds were prepared by electroless Ni-P plating and subsequent annealing processes. Surface structure and crystallinity of NiO film on carbon fiber could be modified by post-annealing at different temperatures (500 and $650^{\circ}C$). Catalytic thermal decompositions of toluene over these catalytic filters were investigated. $500^{\circ}C$-annealed sample showed a higher catalytic reactivity toward toluene decomposition than $650^{\circ}C$-annealed one under same conditions, despite of its lower surface area and toluene adsorption capacity. X-ray diffraction and X-ray photoelectron spectroscopy studies suggest that amorphous structures of NiO on $500^{\circ}C$-annealed catalyst caused the higher reactivity for oxidation of toluene than that of $650^{\circ}C$-annealed sample with a higher crystallinity.

• 대한화학회지
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• 제55권4호
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• pp.666-672
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• 2011

Vanadium 치환체인 polyoxometalate 1, [Cu(2,2'-bipy)]$[Cu(2,2'-bipy)_2]_2[PMo_8V_6O_{42}]{\cdot}1.5H_2O$을 가지고 있는 inorganicorganic complex의 촉매 활성도를 Biginelli 반응에 적용하여 연구하였다. Dihydropyrimidinones를 one-pot 합성하는 반응에서, $H_3PMo_{12}O_{40}$ 촉매 보다[Cu(2,2'-bipy)]$[Cu(2,2'-bipy)_2]_2[PMo_8V_6O_{42}]{\cdot}1.5H_2O$ 촉매가 더 좋은 결과를 나타내었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.165-165
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• 2013

Nickel oxide was deposited on mesoporous silica by atomic layer deposition (ALD) consisting of sequential exposures to Ni(cp)2 and $H_2O$. NiO/silica samples were characterized by inductively coupled plasma-mass spectroscopy (ICP-MS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), etc. The flow-type reactor was used to measure activity of NiO/silica catalyst for catalytic combustion of toluene. The activity of NiO/silica catalyst was evaluated in terms of toluene removal efficiency and selectivity to $CO_2$ and compared with those of bare nickel oxide nanoparticles. In order to investigate influence of reaction temperature on combustion aspect, the catalytic combustion experiments were carried out at various temperatures. We show that both bare and supported NiO can be efficient catalysts for total oxidation of toluene at a temperature as low as $250^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.3105-3108
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• 2011

• 대한화학회지
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• 제52권4호
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• pp.454-456
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• 2008

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1735-1738
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• 2010

• Bulletin of the Korean Chemical Society
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• 제14권2호
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• pp.281-283
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• 1993

Aromatic nitro compounds are selectively hydrogenated to the corresponding amines in high yields at room temperature and atmospheric pressure using BER-Pd catalyst without affecting ketone, ether, ester, nitrile or chloro groups also present. Especially the nitro group in 4-nitrobenzyl alcohol, methyl 4-nitrobenzyl ether and N-N-dimethyl 4-nitrobenzylamine is selectively hydrogenated with this catalyst to give the corresponding amines without hydrogenolysis of benzylic groups. And aromatic nitro compound can be reduced selectively in the presence of aliphatic nitro compound.

• 분석과학
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• 제14권1호
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• pp.72-79
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• 2001

금속포르피린과 그들의 고분자결합 유도체를 산화촉매로 한 2, 4, 6-trichlorophenol(TCP)의 산화분해반응을 수행하였다. 산화제로는 $KHSO_5$와 tert-butylhydroperoxide(TBHP)가 사용되었다. 금속포르피린은 TCP의 산화분해반응에서 매우 낮은 촉매활성을 보인 반면, 금속포르피린이 새로이 합성된 고분자나 XAD2 수지에 화학결합 되어있는 고분자결합 금속포르피린을 촉매로 사용한 TCP의 산화 분해반응에서는 매우 높은 촉매활성을 보여주었다. 또한, 피리딘이나 이미다졸과 같은 전자 주개 리간드가 축방향에 놓여 있는 고분자의 경우에는 더 큰 활성을 나타내었다. Maleic acid와 chloromaleic acid는 생성물로서 ESI-MS로 확인되었다. 특히, XAD2 수지에 결합된 촉매의 경우 산화제에 대한 안정성과 용매에 대한 불용성으로 인해 촉매로서 재사용이 가능함을 확인하였다.

• 대한화학회지
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• 제55권1호
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• pp.14-18
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• 2011

methacrylic acid과 ethylene glycol과의 에스테르화 반응을 ZSM-5에 지지된 heteropolyacids [HPA: $H_4SiW_{12}O_{40}$(STA)와 $H_3PW_{12}O_{40}$(PTA)] 하에서 수행하였다. 비교를 위하여, 지지하지 않은HPA, $H_2SO_4$, $BF_3$와 PTSA 하에서 같은 반응을 수행하였다. 연구한 촉매 중에서, HPA는 $H_2SO_4$, $BF_3$와 PTSA와 비교하여 더 좋은 활성을 보여주었다. 촉매 활성을 HPA지지 ZSM-5 촉매와 비교하였는데, 그 결과 ZSM-5위에 지지된 30 wt% PTA는 bulk PTA와 거의 같은 활성을 나타내었다. 이 반응은 methacrylic acid에 관하여 1차 속도 법칙을 따랐으며, 반응 생성물은 $^1H$-NMR과 FT-IR을 이용하여 확인하였다.