• Journal of Photoscience
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• 제10권1호
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• pp.71-79
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• 2003

Recent advances in photosensitized enantiodifferentiating isomerization and cycloaddition reactions of cycloalkenes (other than cyclooctene) and cycloalkadienes are reviewed.

• Archives of Pharmacal Research
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• 제16권3호
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• pp.251-253
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• 1993

Several new coumarinoyl and coumarionyl-1, 2, 4-triazole derivatives were synthesised via dipolar cycloaddition reactions with 3-coumainohydraziodoyl halide. Structure were based on elemental analysis and spectral data.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1403-1408
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• 2014

The cycloaddition reactions of the N-heterocyclic carbene boryl azide with methyl acrylate, butenone, and hexafluoropropene have been investigated theoretically. Solvent effects on these reactions have been explored by calculation that included a polarizable continuum model (PCM) for the solvent (C6H6). The title reaction could produce 4- and 5-substituted 1,2,3-triazolines, respectively. The reaction systems have the higher chemical reactivity with the low barriers and could be favored. Yet the smaller differences have been found to occur in energetics, and the cycloaddition reactions occur for s-trans conformations over s-cis conformations. The calculations indicated that the cycloaddition reaction of the alkenes have certain regioselectivity.

• Bulletin of the Korean Chemical Society
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• 제29권6호
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• pp.1224-1228
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• 2008

The reaction of internal diynes and cyclopentadiene in the presence of 5 mol % of cobalt catalysts proceeded under 5 atm of carbon monoxide pressure to give a high yield of the corresponding [2+2+2] cycloaddition product. By lowering carbon monoxide pressure from 30 atm to 5atm, cyclopentadiene can be used as a dienophile in the cobalt carbonyl-catalyzed [2+2+2] cycloaddition reaction between internal diynes and cyclopentadiene.

• 한국응용과학기술학회지
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• 제14권3호
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• pp.39-46
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• 1997

Ultraviolet spectrophotometric investigation has been carried out on the rate constants for 1,3-dipolar cycloaddition of 4-substituted-3-phenyloxadiazole derivatives with dipolarophiles such as phenyl acetylene, propiolic acid methyl ester and dimethylacetylene dicarboxylate. From there, the rate constants for 1,3-dipolar cycloaddition were determined at 80, 100 and $120^{\circ}C$, and the reaction rates were increased with increasing temperature. From these rate constants, the values of the thermodynamic activation parameters were obtained. Some thermodynamic activation parameters such as $E_{\alpha}$, ${\Delta}H^{\ast}$, ${\Delta}S^{\ast}$ and ${\Delta}G^{\ast}$ from Arrhenius equation were also calculated for the electrophilic 1,3-dipolar cycloaddition of 3-phenyloxadiazole derivatives with dipolarophiles. In order to the proposal the mechanism and reactivity of 1,3-dipolar cycloaddition reaction, the effect of substituents having various kinds of electron withdrawing or releasing groups were examinated. Considering the effect of substituents, an electron withdrawing group attached at the 4-carbon position in 3-phenyloxadiazole derivatives decreases the reaction rate because of the lack of electron density in 3-phenyloxadiazole ring.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1841-1842
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• 2010

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2517-2518
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• 2009

• 공업화학
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• 제27권3호
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• pp.239-244
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• 2016

본 총설에서는 $CO_2$와 에폭시 화합물의 부가반응에서 무정형, SBA, MCM 또는 상업적으로 쉽게 이용 가능한 다양한 silica 지지체에 담지된 이온성 액체의 촉매적 적용가능성에 대하여 검토하였다. $CO_2$ 부가반응에 의한 5원환 카보네이트의 합성에 대하여 담지된 이온성 액체의 구조적인 영향과 silica 지지체의 종류에 따른 촉매 활성을 검토한 바, 관능기 또는 금속을 보유한 이온성 액체인 경우에 촉매 성능이 개선됨을 알 수 있었다. 또한 silica에 담지된 이온성 액체(SSIL) 촉매의 재사용성과 반응메커니즘을 조사하여 제시하였다.

• 한국응용과학기술학회지
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• 제14권1호
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• pp.95-102
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• 1997

The synthetic method of pyrazole was performed by 1,3-dipolar cycloaddition with dipolarophile instead of the reaction between diazomethane and acetylene. The cycloaddition mechanism and reactivity of 3-phenyloxadiazole derivatives with dipolarophiles was investigated. In order to investigate the mechanism and reactivity of this cycloaddition, the effect of substituents having various kinds of electron withdrawing or releasing groups were examinated. Considering the effect of substituents, an electron withdrawing group attached at the 4-carbon position in 3-phenyloxadiazole derivatives decrease the reaction rate because of the lack of electron density in oxadiazole ring. The reaction rate of 3-phenyloxadiazole derivatives with dipolarophiles were more conveniently measured using UV than using a volumetric analysis which was used before. From the result of this study, it was that the cycloaddition was found to be a first-order reaction depending upon the concentration of 3-phenyloxadiazole only.

• 약학회지
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• 제41권6호
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• pp.714-717
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• 1997

Stereoselective synthesis of the optically active bicyclo [4.2.0] octanone 5 was accomplished using intramolecular olefin-keteniminium salt[2+2]cycloaddition of the amide 4 as a key step. This important chiral synthon was prepared starting from readily available L-glutamic acid via an efficient 8-step sequence.