• Polymer(Korea)
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• v.34 no.6
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• pp.553-559
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• 2010

The paper describes the preparation and characterization of conductive polyaniline-modified polymers by growing of aniline onto functionalized poly(styrene-co-p-methylstyrene) [P(St-co-MSt)]. For this purpose, P(St-co-MSt) was synthesized via nitroxide mediated radical polymerization (NMRP) and then N-boromosuccinimide was used for introduction of bromine to the benzylic positions of copolymer. Afterwards, 1,4-phenylenediamine was linked to the brominated P(St-co-MSt) and functionalized copolymer $[P(St-co-MSt)-NH_2]$ was prepared. The graft copolymerization of aniline monomers onto functionalized P(St-co-MSt) was initiated by oxidized phenylamine groups after addition of ammonium peroxydisulfate (APS), and p-toluenesulfonic acid-doped PANI was chemically grafted onto P(St-co-MSt) via oxidation polymerization. The obtained terpolymer was studied by FTIR and UV-Vis spectroscopy and its thermal behaviour were examined by DSC and TGA analyses. The conductivity of terpolymer was measured by four-point probe method and electroactivity was measured by cyclic voltammetry (CV). The solubility of P(St-co-MSt)-g-PANI was examined in common organic solvents.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2029-2032
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• 2014

Magnetically nano-$CoFe_2O_4$ efficiently catalyzes oxidation of primary and secondary benzylic and aliphatic alcohols to give the corresponding carbonyl products in good yields. The reactions were carried out in an aqueous medium at room temperature in the presence of oxone (potassium hydrogen monopersulfate) as an oxidant. In addition, the catalysts could be reused up to 6 runs without significant loss of activities. Catalyst was characterized by SEM, XRD and IR.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.22 no.1
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• pp.70-83
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• 1996

자외선 차단제는 화장품 원료 중 주요 자극원의 하나이다. 그러나 자오선 차단제를 고분자로 만들 경우 피부에 도포 되었을 때 경피흡수가 불가능 하여 피부 자극 문제를 해결할 수 있다. 이에 본 연구에서는 PVBC와 alkylhydroxycinnamate를 반응시켜 고분자 자외선 차단제를 합성하였다, PVBC는 benzylic chloride를 가지고 있는 고분자로서 이 작용기는 친핵성 치환반응이 용이하므로 side chain modification이 가능하다. PVBC와 alkyl hydroxycinnamate의 반응에서 반응성은 alkyl hydroxycinnamate의 크기와 반응에 첨가된 촉매의 종류에 영향을 받는다. 효율이 낮은 촉매를 사용할 경우에는 alkyl hydroxycinnamate의 크기가 작을수록 반응수율이 높았으며, 높은 효율을 갖는 촉매를 사용할 경우에는 alkyl hydroxycinnamate의 종류에 관계없이 반응수율은 100%였다. 실험에 사용한 PVBC는 평균 분자량이 55,000이었으며, 고분자의 구조와 분자량은 NMR과 GPC로 확인하였다. 고분자 자외선 차단제의 자외선 흡수 능력은 OMC에 비해 65 - 94% 였으며, caprylic/capric triglyceride에 좋은 용해도를 보여주었다.

• Archives of Pharmacal Research
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• v.21 no.1
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• pp.73-75
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• 1998

In summary, six 4-substituted-1-azzanthraquinones were designed and synthesized using hetero Diels-Alder reaction as a key step. Although a great number of reaction conditions for benzylic bromination were examined, this step need to be improved for the efficient synthesis of the related analogues. 4-Bromomethyl-1-azzanthraquinone 6 may have potential for the treatment of tumors resistant to the doxorubicin. The compounds 9 and 10 containing the latent alkylating functionality may need further in depth biological evaluation. Work is in progress to design, synthesize, and evaluate additional compounds in this and related systems.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.658-662
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• 1990

A method for regioselective mono-carbonylation of halobenzyl halide is described. Alkyl halophenylacetate is easily prepared by carbonylating a benzylic halide of halobenzyl halide in the presence of catalytic amount of cobalt carbonyl, a base, and an alcohol under atmospheric pressure of carbon monoxide. The base plays a decisive role in the selectivity of product and NEt$_3$ is the best one among bases used.

• Bulletin of the Korean Chemical Society
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• v.27 no.12
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• pp.2023-2027
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• 2006

Dibenzyl sulfide was oxidized at the a-carbon to yield benzaldehyde in the presence of $Pd(NO_3)_2$. Oxygen itself could not oxidize the sulfide directly, instead the nitrato ligand of the palladium complex transferred oxygen to dibenzyl sulfide to form benzaldehyde. The X-ray crystal structure of the intermediate complex, cis-[$Pd(NO_3)_2${$S(CH_2C_6H_5)_2$}$_2$], revealed that the nitrato ligand was unidentate. Para-substituted dibenzyl sulfides I, $(YC_6H_4CH_2)_2S $wherein Y = $OCH_3$, $CH_3$, Cl, CN, or $NO_2$, were synthesized and reacted with palladium nitrate, and those with electron-donating substituents (Y = $OCH_3$ and $CH_3$) were good substrates for the oxidation reaction with palladium nitrate. Thus, the reaction mechanism of the oxygen transfer was proposed to include nucleophilic benzylic carbon.

• Journal of the Korean Chemical Society
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• v.41 no.10
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• pp.535-540
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• 1997

Potassium carbonate reacts with silicon tetrachloride to form trichlorosilyloxy carbonylchloride which reacts subsequently with another molecule of silicon tetrachloride leading to phosgene eventually in chlorinated solvents. This in situ generated trichlorosilyloxy carbonylchloride or phosgene were found to be very effective for the chlorination of a wide variety of alcohols to the corresponding chlorides. Primary, secondary and benzylic alcohols were converted into corresponding chlorides when treated with silicon tetrachloride in the presence of potassium carbonate at room temperature.

• Archives of Pharmacal Research
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• v.28 no.4
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• pp.382-390
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• 2005

chial allylic ethers with a hydroxyl group attached to the $\pi-system$ and chlorosulfonyl isocyanate. The enantioselectivity of the CSI reaction with the chiral allylic and benzylic ethers was examined in various solvents and temperatures. Based on these results, it was proposed that the CSI reaction is a competitive reaction of a $S_{N}i$ (retention) and a $S_{N}1$ mechanism (racemization) according to the stability of the carbocation intermediate. This means that there is a greater proportion of retention with the less stable the carbocation intermediate and vise versa.

• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.45-48
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• 1992

A synthetic method for bis-carbonylation of bromo(bromomethyl)benzenes was described. Alkyl carboalkoxyphenylacetates were easily prepared by the carbonylation of benzylic and arylic bromide moieties in bromo(bromomethyl)benzenes with alcohols in the presence of $K_2CO_3,\;CH_3I$, and a catalytic amount of cobalt carbonyl under the atmospheric pressure of carbon monoxide at room temperature in good to excellent yields. The base played a decisive role in the selectivity of product and $K_2CO_3$ was the best one among bases used.

• Bulletin of the Korean Chemical Society
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• v.4 no.3
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• pp.120-123
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• 1983

The reaction of hexacyanoferrate (Ⅲ) with nitrotoluenes in aqueous acetic acid containing perchloric acid(1.0 M) at $50^{\circ}C$ gave the corresponding aldehyde as the major product. The order with respect to each of the reactants ― substrate, oxidant and acid ― was found to be unity. The Hammett plot yielded a ${\sigma}^+$ value of -1.30, and the kinetic isotope effect gave a $k_H/k_D$ value of 6.2. The pathway for the conversion of the nitrotoluenes to the products has been mechanistically visualized as proceeding through the benzylic radical intermediate, formed in the rate determining step of the reaction.