• 대한화학회지
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• 제9권2호
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• pp.88-95
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• 1965

퓨란, 醋酸풀퍼릴, 풀퍼릴알코올과 마레인酸無水物을 에틸 에테르 存在下에서 附加反應시켜 exo附加物을 만들고 이 化合物들에 對한 臭素化反應을 물 存在下에서 行한 바 各各 모노부롬化락톤 및 디브롬酸을 生成하였으며 락톤의 生成收率은 轉位된 carbonium ion에 對한 carboxylic acid의 反應기여(participation)에 依하여 決定되면 化合物 自體의 立體條件(steric requirement)이 그 기여에 영향을 준다는 것을 究明하였다. 퓨란附加物을 有機溶媒(四鹽化炭素, 메틸렌크로라이드)存在下에서 臭素化反應하면 二臭化物이 生成하고 光線 存在下에서 鹽素化反應하면 四鹽化反應物이 生成됨을 究明하였다. 各 化合物의 合成方式 및 反應過程에 關하여 論及하였다.

• Journal of Photoscience
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• 제8권2호
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• pp.70-73
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• 2001

The chlorin-bromine building block was constructed and applied to synthesize $\delta$-bromo compounds of methyl pyropheophorbide-a. The visible spectra of the title compounds were discussed.

• Bulletin of the Korean Chemical Society
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• 제29권9호
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• pp.1800-1802
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• 2008

• Bulletin of the Korean Chemical Society
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• 제19권1호
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• pp.74-78
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• 1998

Synthesis of novel 9-fluoroanthracyclines carrying L-fucose as a sugar component is described. Compound 3 containing a fluorine at the C-9 position was synthesized from an epoxide 2 and HF/Pyr (7 : 3). Bromination and hydrolysis of compound 3 resulted in synthesis of an aglycone, 9-fluoroanthracyclinone 6. The α-(1b) and β -anomers (1a) of the final product were obtained in high yields by a coupling reaction with the L-fucose.

• Bulletin of the Korean Chemical Society
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• 제7권3호
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• pp.210-213
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• 1986

1,1-Dicyano-2-ethoxycyclobutane (1a) was prepared by [2 + 2] cycloaddition reaction of vinylidene cyanide with ethyl vinyl ether. 1,1-Dicyano-2-phenylcyclobutane (1b) was prepared by the reactions involving the reduction of cinnamyl alcohol, chlorination, cyanomethylation, bromination, and ring-closure reaction. Compound 1a was ring-opening polymerized with NaCN or n-butyllithium to give a low molecular weight polymer. The compound 1b however, failed to polymerize by either anionic or radical catalysts.

• Bulletin of the Korean Chemical Society
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• 제6권6호
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• pp.348-350
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• 1985

The compound 1,1,3,4-tetramethyl-1-sila-3-cyclopentene was obtained through the reaction of 2,3-dimethylbutadiene and dichlorodimethyl-silane in THF in the presence of sodium metal. After the bromination of this compound at $0^{\circ}C$ for 2 hrs and dehydrobromination by using a base, we prepared 1.1.3.4-tetramethyl-1-sila-2,4-cyclopentadiene, Which could undergo dimerization. The identification has been done by using $^1H-,^{13}C-$ and C/H-Correlation two dimensional nmr spectroscopies.

• Bulletin of the Korean Chemical Society
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• 제16권4호
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• pp.349-355
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• 1995

Bromo-and chlorotrimethylsilane react with selenium dioxide in halocarbon solvents and generate selenium oxybromide and oxychloride, respectively. These in-situ generated oxyhalides turned out to be very efficient for selective bromination and chlorination of aldehydes and ketones. Under carefully controlled reaction conditions, second and third introduction of halogens into carbonyl compounds can be greatly suppressed, and high yields of monohalo compounds were obtained. The product ratios of this halogenation reactions can be best explained if the reactions are assumed to involve intermediate β-ketoselenenyl chlorides.

• 멤브레인
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• 제27권6호
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• pp.528-535
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• 2017

본 연구에서는 폴리페닐렌옥사이드 고분자에 브롬화반응을 통해서 할로겐 원소를 수월하게 도입하고, 도입한 할로겐 원소를 이미다졸륨으로 치환하여 이미다졸륨이 도입된폴리페닐렌옥사이드를 합성하였다. 다양한 특성평가를 통해서 합성이 이루어졌음을 확인하였고, 산소, 질소, 이산화탄소 기체투과 특성평가를 진행하여 합성한 고분자의 기체특성을 확인하였다. 이미다졸륨의 함량이 증가할수록 합성고분자의 이온교환용량이 증가하였으나, 기계적 강도는 감소하였다. 특히, 기체투과도는 미세하지만 감소하는 경향을 나타내었으며, 이산화탄소/질소 선택도의 경우 이미다졸륨 함량이 높아질수록 증가하는 경향을 확인할 수 있었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권3호
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• pp.130-137
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• 2002

Microbial lactonohydrolases (intramolecular ester bond-hydrolyzing enzymes) with unique properties were found. The lactonohydrolase from Fusarium oxysporum catalyzes enantiose-lective hydrolysis of aldonate lactones and D-pantoyl lactone (D-PL). This enzyme is useful for the large-scale optical resolution of racemic PL. The Agrobacterium tumefaciens enzyme catalyzes asymmetric hydrolysis of PL, but the stereospecificity is opposite to that of the Fusarium enzyme. Dihydrocoumarin hydrolase (DHase) from Acinetobacter calcoaceticus is a bifunctional enzyme, which catalyzes not only hydrolysis of aromatic lactones but also bromination of monochlorodi-medon in the presence of H$_2$O$_2$and dihydrocoumarin. DHase also hydrolyzes several linear esters, and is useful for enantioselective hydrolysis of methyl DL-$\beta$-acetylthioisobutyrate and regioselective hydrolysis of methyl cetraxate.

• Bulletin of the Korean Chemical Society
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• 제24권4호
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• pp.460-466
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• 2003

For the drug master file (DMF) of ketoconazole, four impurities (1-4) contained in ketoconazole were synthesized. During the synthesis of 2, a new synthetic method of 1,4-dihydropyrazine was established. To oxidize the aminoalcohol (2j) to the aminal (2j-1), the standard Swern oxidation condition was modified to mask the nucleophilicity of the amino group temporarily using one equivalent of acetic acid. Derivative 3 was synthesized via regioselective bromination at the 2 position of the 4-aminophenol derivative (3a) using $Br_2$ in the presence of p-TsOH. The etherification of aryl bromide with the phenol derivative (1f) was accomplished by a modification of the general Cu-mediated reaction condition using excess 1f itself as a solvent at elevated temperature (190 ℃).