• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.171-176
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• 1996

The easily biodegradable nonionic surfactant of glucamide(N-alkyl-N-acyl glucamine) was synthesized by the two-step reaction. The first step was the amination between alkylamine and glucose in methanol. Then, alkyl glucamines were obtained by reduction using Ni catalyst under the high pressure with 86~93% of reaction yield. The second step was the synthesis of glucamide from alkyl glucamine and fatty acid methyl ester in methanol under the alkali catalytic condition while refluxing the solvent. The reaction yield of this step was 84~95% except the benzyl glucamine, which the reaction yield was 50~70%. The molecular structure of four kinds of alkyl glucamine and 16 kinds of glucamide with different alkyl and acyl groups was studied by IR, MS and NMR.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.1
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• pp.17-27
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• 2001

플라티늄포르피린 핵과 주위에 8, 16, 32 그리고 64 개의 벤질 단위를 갖는 새로운 덴드리머를 압력 감지형 페인트에 사용할 발광체로 합성하였다. 플라티늄포르피린 핵을 갖는 제 1 세대의 덴드리머는 Lindsey형 합성법을 이용하여 제조하였으며, 제 2 세대에서 제 4 세대까지의 플라티늄포르피린 핵을 갖는 덴드리머는 플라티늄 테트라키스(3,5-디히드록시페닐)포르피린을 적합한 덴드론 브로마이드와 Williamson 에테르 합성법에 따라 알킬화반응시켜 제조하였다. 이러한 에테르 연결의 생성 반응들은 $K_2$CO$_3$와 18-크라운-6를 사용하여 아세톤 용매에서 질소 기류 하에서 6$0^{\circ}C$에서 수행하였을 때 가장 좋은 결과를 주었다. 그리고 이렇게 합성한 덴드리머들을 $^1$H-NMR, $^{13}$C-NMR, Mass spectrum 이용하여 구조를 확인하고, 그리고 UV-VIS spectroscopy를 이용하여 분광학적인 특성을 조사하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.499-505
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• 2013

Cr(VI)-4-(dimethylamino)pyridine[4-(dimethylamino)pyridinium chlorochromate] was synthesized by the reaction of 4-(dimethylamino)pyridine with chromium trioxide in 6M-HCl, and characterized by IR, ICP. The oxidation of benzyl alcohol using 4-(dimethylamino)pyridinium chlorochromate in various solvents showed that the reactivity increased with the increase of the dielectric constant(${\varepsilon}$), in the order: cyclohexene$H_2SO_4$ solution), 4-(dimethylamino)pyridinium chlorochromate oxidized benzyl alcohol and its derivatives(p-$OCH_3$, m-$CH_3$, H, m-$OCH_3$, m-Cl, m-$NO_2$) smoothly in DMF. Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant(${\rho}$) was -0.68(303K). The observed experimental data was used to rationalize the hydride ion transfer in the rate-determining step.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.663-667
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• 2013

$Ag/TiO_2$ particle was prepared using various ionic liquids by wet impregnation. The properties of the particles were significantly affected by the composition of ionic liquids. This is mainly attributed to different abilities of an ionic liquid to coordinate with the silver particle, leading to various coagulation of silver particles. The catalytic activity of the prepared samples was examined for the aerobic benzyl alcohol oxidation. Among the particles, $Ag/TiO_2$ prepared with 1-octyl-3-methylimidazolium tetrafluoroborate showed the best catalytic performance.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.200-204
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• 2010

Surface properties are important for determining the functions and uses of materials. So modification of materials with polymer thin films has emerged as an important method to control the physical and chemical properties of the surface layer. We report a simple and effective method to photochemically attach thin polymeric layers to solid surface without chemical derivatization of the substrate and/or the polymer. The system is based on a photoreactive poly(4-vinylpyridine) (P4VP) thin film which is formed on the $SiO_{2}$ surface via spin coating. This substrate is then covered with another polymer film that is reacted with the benzyl radical moieties by UV irradiation. As a result of photochemical reaction, a thin layer of the later polymer is covalently bound to the surface of P4VP. Unbounded polymer is removed by sonication. The thickness of the attached film is a function of the irradiation time and the molecular weight of the polymer. Spatially defined polymer thin films can be fabricated by way of photolithography.

• Nuclear Engineering and Technology
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• v.5 no.4
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• pp.321-333
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• 1973

The rates and activation parameters for the halide exchange reactions of substituted benzenesulfonylbromides (R-C$_{6}$H$_4$SO$_2$Br, R=p-MeO, p-$CH_3$, p-H, p-NO$_2$) in dry acetone at two temperatures were determined. It was found that the nucleophilicity order of Cl->I-$\geq$Br- for strong electron withdrawing-, and mild electron donating group, and of I-$\geq$Cl->Br- for strong electron donating group, Hammett plots showed slightly convoked characteristics which is similar to the plots of substituted benzenesulfonylchlorides, but contrary to the concaved nature for the halide exchange reactions of substituted benzyl chlorides. The rate of halogen exchange between benzenesulfonylbromide and lithium bromide decreased in the order of solvent : ($CH_3$)$_2$CO>$CH_3$CN》MeOH. The rates and activation parameters were also compared with those already known in the substituted benzenesulfonylchlorides. Theses were explained in terms of the structural properties of the transition state, and discussed the reaction mechanisms.s.

• Journal of the Korean Applied Science and Technology
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• v.29 no.3
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• pp.429-434
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• 2012

A kind of Antihistamines, Azelastine HCl which known as modern H1-blockers, was synthesized by four step process using phthalic anhydride, 4-chlorophenylacetic acid, hydrazine 2HCl. The first step was the reaction of removing carboxyl group and hydroxyl group and the second step was saponification of 3-(4-chlorobenzylidene)phthalide. The third step was the nucleophilic addition reactions of primary amines and the fourth step was addition reaction of N-methyl-1-aza-bicyclo[3,2,0]heptane to 4-(4-chlorobenzyl)-1-(2H)phthalazinone. As a result, product was analyzed by FT-IR and $^1H$-NMR and could be obtained with a yield of 80%.

• Journal of the Korean Chemical Society
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• v.27 no.1
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• pp.46-52
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• 1983

Selective reduction of halide (Br, I) with lithium borohydride in halogen compounds containing chloro, nitro, ester and nitrile groups was achieved satisfactorily. 1-Bromo-4-chlorobutane was reduced to 1-chlorobutane in 96% yield and the reduction of p-nitrobenzyl bromide gave p-nitrotoluene in 98% yield. However, the selectivity on the reduction of ethyl 3-iodopropionate and 4-bromobutyronitrile required the presence of equimolar pyridine to give good yield of ethyl propionate (93%) and n-butyronitrile (88%), respectively. In competitive reduction of 1-bromoheptane and 2-bromoheptane, lithium borohydride reduced 1-bromoheptane preferentially in the molar ratio of 93:7.

• Polymer(Korea)
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• v.24 no.6
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• pp.757-762
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• 2000

Vinylbenzyloxystyrylpyridine (VSP) as a photosensitive monomer was synthesized by the reaction of 4-hydroxystyrylpyrydine with 4-vinylbenzyl chloride. Photocrosslinkable polymers containing rosin moiety were then prepared by radically copolymerizing VSP with a methacrylic monomer having rosin moiety. In these copolymerizations, the VSP feed ratios of 5 to 20 mol% were used. The contents of VSP units in the copolymers were determined by UV spectroscopy to be 5.3 to 17.3 mol%. The numberaverage molecular weights of these polymers were in the range of 18000 to 28000 and the polydispersity indexes were about 1.8. The glass transition temperatures were about 15$0^{\circ}C$ and the initial decomposition temperatures were about 34$0^{\circ}C$. The polymers were relatively fast photocrosslinked and the photocrosslinking reaction could be traced by the UV spectroscopy and the residual yield method.

• Journal of the Korean Chemical Society
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• v.31 no.5
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• pp.419-424
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• 1987

Kinetic studies on the solvolysis of para-methyl benzyl nitrate and benzyl nitrate were carried out in aqueous methanol, ethanol, acetonitrile, acetone, tetrahydrofuran and dioxane mixtures at 60$^{\circ}$C. The rates were faster in protic solvent mixtures than in aprotic solvent mixtures. This was considered in the light of transition state stabilization by hydrogen bonding solvation of protic solvent mixtures. Grunwald-Winstein equation, extended Grunwald-Winstein equation and correlation between E$_T$(30) and rate constant were applied in order to discuss the transition state variations caused by changing benzyl substituents and solvents. The results showed that strong electrophilic assistance of solvent is operative in the the water-rich solvents.