• Bulletin of the Korean Chemical Society
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• 제27권5호
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• pp.769-772
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• 2006

• 대한화학회지
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• 제30권2호
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• pp.237-242
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• 1986

4-bromoiodobenzene 또는 4-diiodobenzene과 2 당량의 아크릴산 유도체들간의 트리에틸아민 존재하의 팔라듐 촉매를 이용한 비닐화 반응에 의해 (E,E)-p-Phenylene diacrylic acid유도체들을 비교적 좋은 수득율로 쉽게 얻을 수 있었다. 이들 반응에서 4-diiodobenzene이 4-bromoiodobenzene보다 더 좋은 반응성을 나타냈으며 이들 반응들은 입체특이성있게 진행되었다. 또한, 사용된 촉매에 다른 4-bromoiodobenzene의 선택적인 비닐화 반응을 이용하여 (E,E)-p-Phenylene diacrylic acid유도체들과 이외에 몇가지 1,4-diolefinic aromatic compounds를 편리하게 합성할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제25권11호
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• pp.1611-1612
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• 2004

• Bulletin of the Korean Chemical Society
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• 제7권2호
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• pp.142-145
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• 1986

Vinylation of highly hindered ${\beta}$-acetoxyvinyl mercurials with olefins in acetonitrile at room temperature in the presence of cupric chloride, as a reoxidant for the palladium, and a catalytic amount of $LiPdCl_3$ gave the corresponding conjugated dienes in moderate to good yields. The (E) or (Z) geometry in vinyl mercurials was retained in the vinylated products. The reaction was tolerant of a wide variety of functional groups ($CO_2$R, CN, OR, OAc) on either the vinyl mercurial or olefin compounds.

• Bulletin of the Korean Chemical Society
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• 제13권4호
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• pp.354-355
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• 1992

• Archives of Pharmacal Research
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• 제27권11호
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• pp.1132-1135
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• 2004

In order to find new tyrosinase inhibitors and the effects of prenyl residue on flavonoid molecules, eight prenylated and three synthetic vinylated flavonoids were examined on their inhibitory effect against tyrosinase activity. From the results, kuwanon C, papyriflavonol A, sanggenon D and sophoflavescenol were found to possess the considerable inhibitory activity. Especially, sanggenon D is revealed as a potent inhibitor ($IC_{50}$ =7.3$\mu$ M), compared to the reference compound, kojic acid ($IC_{50}$ =24.8 $\mu$M). However, the prenylation with isoprenyl group or the vinylation to flavonoid molecules did not enhance tyrosinase inhibitory activity.

• Bulletin of the Korean Chemical Society
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• 제7권3호
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• pp.235-237
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• 1986

Reaction of $(E)-{\beta}-chloro-{\gamma}$-hydroxyvinylmercurials, prepared by mercuration of propargyl alcohol and 2-methyl-3-butyne-2-ol, with olefins in the presence of a catalytic amount of $Li_2PdCl_4$ and 2 equiv of cupric chloride in methanol at $50^{\circ}C$ gave the corresponding (E,E)-2,4-dienols in moderate yields. However, addition of 1 equiv of inorganic bases such as magnesium oxide to the reaction mixture brings a rapid and clean vinylation and gave high yields of the dienols at room temperature. In the case of hindered (E)-2-chloro-3-chloromercuri-2-buten-1,4-diol prepared from 2-butyne-1,4-diol, reaction with olefins gave the dienols only in low yields even in the presence of 2 equiv of magnesium oxide.

• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.246-250
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• 1987

The reaction of aryl iodides or bromides with olefins in the presence of 1 mol % of $PdCl_2(PPh_3)_2$ and 3 equiv. of $n-Bu_3N\; at\; 100^{\circ}C$ in carbon monoxide atmosphere gave the corresponding aryl vinyl ketones in good yields with small amount of vinylated 1-aryl olefins. But, when the reaction was proceeded under the 10 atm of carbon monoxide, aryl vinyl ${\alpha}$-diketones and aryl vinyl ketones were obtained in moderate to good yields. The reaction was tolerant of a wide variety of functional groups on either the aryl halides or olefin compounds. Reactivity of aryl halide decrease in the order; aryl iodide > aryl bromide ${\gg}$aryl chloride. In general, the reaction proceeded well and gave good yields of aryl vinyl ketones and aryl vinyl ${\alpha}$-diketones when reactants are substituted with electron withdrawing groups.

• 터널과지하공간
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• 제14권2호
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• pp.108-120
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• 2004

발파작업으로 인해 발생하는 발파진동이 암반 및 주위 구조물에 미치는 영향을 분석하기 위한 동하중해석이 최근 급격히 증가하고 있다. 하지만 일반적인 동하중 해석은 발파압력이력곡선을 통하여 얻어진 발파하중을 입력 자료로 사용하고 있으므로 복잡한 지질 구조를 갖는 암반에 대해서는 그 신뢰도가 떨어지고 있다. 이에 본 연구에서는 해석 대상 지역에서의 발파작업을 통해 직접 획득된 발파진동파형을 그대로 입력 자료로 활용하였으며, 인도네시아 Pasir 노천 채광장에 대한 현장 적용을 통해 사면의 현재 상황을 수치 해석적으로 정확히 모사함으로써 발파진동파형을 입력 자료로 활용하는 기법에 대한 검증이 가능하였다.