• 공업화학
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• 제3권2호
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• pp.288-295
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• 1992

Triirondodecacarbonyl에 의한 니트로벤젠의 환원 반응에 상 이동 촉매를 사용한 결과 상온에서 높은 수율의 아닐린을 합성할 수 있었다. Benzyltriethylammonium chloride, tricaprylmethylammonium chloride, 18-crown-6, polyethyleneglycol-400 등이 이 반응에 좋은 상 이동 촉매임을 알 수 있었고, 반응온도, 수용액상의 NaOH 농도, 유기용매가 반응속도 및 아닐린의 수율에 미치는 영향을 고찰하였다.

• 대한방사성의약품학회지
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• 제7권2호
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• pp.141-146
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• 2021

With increasing interest in fluorinated compounds, nucleophilic fluorination reaction has been generally used for synthesizing fluorine-containing chemicals. However, alkali metal fluorides (MFs) generally have low solubility and reactivity in organic solvent. To overcome these problems, various phase transfer catalysts (PTCs) have been investigated. Calix-arene is known as to capture the metal cation(M⁺), and therefore in this review, we would like to introduce several kinds of calix-arene based PTCs, such as bis-tert-alcohol-functionalized crown-6-calix[4]arene (BACCA), oligo-ethylene glycol linked bis-triethyleneglycol crown-5-calix[4]arene (BTC5A), and ionic liquid functionalized calix-arene based catalyst, as well as ion-pair receptor crown-6-calix[4]arene-capped calix[4]pyrrole.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.250.3-251
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• 2003

A series of cinchona alkaloid-derived dimeric quaternary ammonium salts were prepared as chiral phase-transfer catalysts by the introduction of various functional groups on the phenyl ligand. Among them. the 2-F-substituted derivative 21 showed the highest enantioselectivity in the alkylation of the glycine anion equivalent 1 (97->99 ％ ee).

• 대한방사성의약품학회지
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• 제3권2호
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• pp.116-121
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• 2017

To overcome the low reactivity and solubility of alkali metal fluorides (MFs), various types of phase transfer catalysts (PTCs) have been developed over the last decades. However, since the fluoride activated by such PTC sometimes has a strong basicity, it may cause various side reactions such as elimination reaction or hydroxylation reaction in the nucleophilic fluorination reaction. Also, they may cause separation problems in the compound purification process. In recent advanced study, various PTCs have been developed to solve these problem of conventional catalyst. In this review, we would like to introduce three kinds of novel multifunctional organic catalysts such as bis-tert-alcohol-functionalized crown-6-calix[4]arene (BACCA), easy separable pyrene-tagged ionic liquid (PIL) by reduced graphene oxide (rGO), and tri-tert-butanolamine organic catalyst.

• Bulletin of the Korean Chemical Society
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• 제25권3호
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• pp.347-348
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• 2004

• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2289-2292
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• 2010

Long chain dicationic ammonium salts were used successfully as phase transfer catalyst in the condensation reactions of aromatic aldehydes in water under ultrasonic irradiation for the first time. The quaternary salt having longer distance between the cation centers was more effective than the mono- and dicationic ones having short chain.

• 공업화학
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• 제4권4호
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• pp.715-720
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• 1993

보통의 산화조건에서는 산화되기 어려운 diphenylmethane (pKa=33.4)을 상이동 촉매와 고체인 potassium tert-butoxide 를 염기로 사용하여 상온과 상압에서 산화시켜 benzophenone 을 합성하였다. 4급염인 benzylytriethylammonium chloride, tetrabutyl ammonium bisulphate, tetrabutylphosponium chloride 등은 이 반응에 활성이 없었으나 18-crown-6와 폴리에틸렌글리콜은 촉매활성을 나타내었다. 같은 무게나 같은 몰수의 폴리에틸렌글리콜을 상이동 촉매로 사용한 경우 모두에서 diphenylmethane 의 전화율은 폴리에틸렌글리콜의 사슬길이가 길수록 증가하였다. Diphenylmethane 의 반응속도는 교반속도가 클수록 증가하였고, 비양성자성 용매인 DMF 를 사용한 경우가 벤젠을 용매로 사용한 경우보다 높은 반응속도를 나타내었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.33-36
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• 2007

Currently, many structured catalysts using microchannel are researched to apply to fuel reforming. In this paper, ceramic monolith and metal mesh as structured catalysts are investigated for catalytic autothermal reforming. When GHSV increases, each structured catalyst has better performances(hydrogen production, fuel conversion) than packed bed catalyst for autothermal reforming. The major causes seem to be the elevated heat and mass transfer, gas phase reaction and redistribution of packed bed due to high pressure drop.

• Bulletin of the Korean Chemical Society
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• 제13권3호
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• pp.274-279
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• 1992

Immobilization method of lariat azacrown ethers, containing hydroxyl group in the side arm of crown ring, on the polymer matrix and the phase-transfer catalytic activity of thus obtained immobilized lariat azacrown ethers were studied. Polystyrene resins with crown ether structures and hydroxyl groups adjacent to the macrorings were prepared by the reaction of crosslinked polystyrene resins containing epoxy groups with monoaza-15-crown-5 or monoaza-18-crown-6. Microporous crosslinked polystyrene resins containing epoxy group for the syntheses of these immobilized lariat crown catalysts were prepared by suspension polymerization of styrene, divinylbenzene (DVB 2%) and vinylbenzylglycidyl ether. The immobilized lariat catalysts with 10-20% ring substitution exhibited maximal activity for the halogen exchange reactions of 1-bromooctane with aqueous KI or NaI under triphase heterogeneous conditions. Immobilized catalyst exhibited higher activity than corresponding catalyst without the hydroxyl group and this result was suggested that the active site have a structure in which the $K^+$ ion was bound by the cooperative coordination of the crown ring donors and the hydroxyl group in the side arm.

• 공업화학
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• 제7권1호
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• pp.26-33
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• 1996

본 연구는 이산화탄소와 phenyl glycidyl ether(PGE)의 부가반응에 대하여 상이동 촉매의 특성을 고찰한 것이다. 4급 암모늄염 상이동 촉매의 경우 알킬기의 크기가 크고 짝이온의 친수성이 강할수록 좋은 촉매활성을 나타내었다. 폴리에틸렌글리콜과 crown ether도 NaI와 함께 사용한 결과 효율적인 촉매임을 알 수 있었다. 이산화탄소의 압력이 증가하면 용매인 NMP에 대한 $CO_2$의 용해도가 증가하여 PGE의 전화율이 증가하였다. 또한 상이동 촉매의 역할이 포함된 반응메카니즘을 제시하였다.