• Journal of the Korean Applied Science and Technology
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• v.16 no.2
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• pp.117-125
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• 1999

The alkylation benzene with 1-dodecene of Mordenite, Zeolite ${\beta}$ and Zeolite Y was studied in the stirring batch reactor. The kinds of zeolites were found to have influenced the reaction conversion and distribution of phenyldodecane isomer in the product. Compared to the alkylation conducted over Zeolite Y and Zeolite ${\beta}$, the alkylation over Mordenite exhibited higher distribution of 2-phenyldodecane and the alkylation conducted over Zeolite Y and Mordenite, the alkylation over Zeolite ${\beta}$ exhibited higher distribution of heavy alkylate which formed through oligomerization reaction readily deactivated the Lewis acid sites. A special feature of the effect of the benzene to 1-dodecene ratio the reaction conversion and selectivity of phenyldodecane isomer was found. At alkylation of benzene with 1-dodecene over Zeolite ${\beta}$, when the catalyst content in the system was high, the reaction will reach the optimal conversion at the higher B/D. When the benzene to 1-dodecene ratio was high, the selectivity of phenyldodecane isomer is high. It was also found that at the similar reaction conversion there was the same product distribution regardless of D/C ratio.

• Bulletin of the Korean Chemical Society
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• v.22 no.9
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• pp.1056-1058
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• 2001

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4133-4136
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• 2011

• Journal of the Korean Chemical Society
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• v.60 no.5
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• pp.374-377
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• 2016

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.323-326
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• 2011

HZSM-5, synthesized in fluoride medium, showed high selectivity for the formation of 1,4-diethylbenzene (1,4-DEB) in the vapour phase ethylation of ethylbenzene (EB) with ethanol and hence becomes a convenient eco-friendly substitute for hazardous mineral acid catalysts. De-ethylation of EB to benzene was also minimized over this catalyst. As the medium pore size and presence of weak and medium acid sites might be the cause of such benefits, fluoride mediated synthesis of ZSM-5 is proven to be advantageous for para-selective alkylation of alkyl aromatics.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.895-901
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• 1999

The acid characteristics of ${\beta}$-zeolites was modified by the different calcination conditions in order to remove template and the post-treatments such as ammonium ion exchange and HCl treatment. Alkylation of benzene with propene and isopropanol was carried out over the catalysts to investigate the effect of acid characteristics on the selectivity to cumene in this reaction. The $Br{\ddot{o}}nsted$ acidity(IR $3610cm^{-1}$ band) of ${\beta}$-zeolite was significantly reduced by a deep bed calcination compared to that of ${\beta}$-zeolite calcined in a shallow bed. Moreover, extraframework aluminum species which did not show acidity were produced by the framework dealumination on the deep bed calcined ${\beta}$-zeolite. $Br{\ddot{o}}nsted$ acidity of deep bed calcined ${\beta}$-zeolite was significantly recovered by ammonium ion exchange, however, it was partially recovered by a weak HCl treatment. It was found that the framework aluminum as well as the extraframework aluminum were extracted by a strong HCl treatment. The selectivity to cumene was shown to be about 95% on the shallow bed calcined ${\beta}$-zeolite, however, it decreased to 90% on the deep bed calcined one. The post-treatment such as ammonium exchange and weak HCl treatment enhanced the selectivity to cumene up to 93% by the partial recovery of $Br{\ddot{o}}nsted$ acidity. Propene was proved to be a good alkylating agent for the selectivity to cumene compared to isopropanol.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.43 no.2
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• pp.115-124
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• 2017

The objective of this study was to investigate skin whitening effect of Resorcinol dipentyl ether [1,3-di(pentyloxyl)benzene] by in vitro experiments. Resorcinol dipentyl ether was prepared by alkylation of resorcinol with 1-bromopentane. The reaction products were confirmed by NMR, MS and other analytical equipments. In order to evaluate the skin safety of resorcinol dipentyl ether, the cytotoxicity of the cells constituting the skin (keratinocyte, melanocyte, fibroblast) was analyzed and similar cell viability was observed in all cell lines as compared with the control group. Inhibition of extracellular melanin synthesis effect of resorcinol dipentyl ether was approximately 65.75% at $20{\mu}g/mL$ and inhibition of intracellular melanin synthesis effect of resorcinol dipentyl ether was approximately 53.89% at $20{\mu}g/mL$. The real-time PCR and western blot analysis of mRNA expression and protein expression of tyrosinase, TRP-1, and TRP-2 related to melanogenesis revealed that melanin inhibitory effect of resorcinol dipentyl ether was inhibited from the transcription stage respectively. Finally, this study suggested applicability of Resorcinol dipentyl ether [1,3-di(pentyloxyl)benzene] as a whitening functional cosmetic new material.

• Journal of the Korean Chemical Society
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• v.36 no.4
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• pp.579-583
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• 1992

Stereoselective synthesis of farnesol, (2E, 6E)-3,7,11-trimethyldodeca-2,6,10-tiren-1-ol(1), was carried out using 5-bromo-2-methylpent-2-ene(2) as a starting material. After conversion of 5-bromo-2-methylpent-2-ene(2) to the corresponding iodide compound, 5-(4-methylpent-3-enyl)-2,3-dihydrofuran(4) was obtained by alkylation of 5-lithio-2,3-dihydrofuran with 5-iodo-2-methylpent-2-ene. Ni(0)-catalyzed coupling reaction of the dihydrofuran 4 with MeMgI was proceeded to give (3E)-4,8-dimethylnona-3,7-dien-1-ol(5) in 72% yield. The resultant homoallylic alcohol 5 was converted to the (5E)-6,10-dimethylundeca-5,9-dien-2-one(8) in 4 steps. Compound 8 was condensed with dimethylmethoxycarbonylmethylphosponate in benzene follwed by $NaBH_4$ reduction in EtOH to yield (2E, 6E)-3,7,11-trimethyldodeca-2,6,10-trien-1-ol(1). Ni(0)-catalyzed coupling reaction of MeMgI with dihydrofuran 4 was a key step in this synthesis of farnesol(1).