• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.769-772
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• 2006

• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.237-242
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• 1986

(E,E)-p-Phenylene diacrylic acid derivatives were prepared in moderate to good yields by the palladium catalyzed vinylation of 4-bromoiodobenzene or 4-diiodobenzene with 2 equiv of acrylic acid derivatives in the presence of triethylamine. 4-Diiodobenzene was more reactive than 4-bromoiodobenzene in the above reactions and the reactions were proceeded stereospecifically. (E,E)-p-Phenylene diacrylic acid derivatives and several other 1,4-diolefinic aromatic compounds were also synthesized by utilizing the selective vinylation of 4-bromoiodobenzene.

• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1611-1612
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• 2004

• Bulletin of the Korean Chemical Society
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• v.7 no.2
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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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• v.13 no.4
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• pp.354-355
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• 1992

• Archives of Pharmacal Research
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• v.27 no.11
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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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• v.7 no.3
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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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• v.8 no.4
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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.

• Tunnel and Underground Space
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• v.14 no.2
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• pp.108-120
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• 2004

Dynamic analysis has been increased recently to analyze the effect of the blasting vibration on the rock mass as well as the surrounding structures. The major input parameter far the general dynamic analysis, however, is merely the blasting pressure which can be obtained from the blasting pressure-time history curves. But in case of the complicate geological condition it is not simple to apply the blasting pressure on the numerical analysis because e ground vibration characteristics should be obtained considering the complexity of ground condition. Therefore the authors tried to use the blasting vibration waveform as an input data This vinylation frequency could be obtained from the test blasting in the Pasir mine, Indonesia. Through the dynamic numerical analysis on the slopes in Pasir, the current situation of this slope could be simulated precisely.