• 한국산업융합학회 논문집
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• 제12권3호
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• pp.143-147
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• 2009

The enantioselective reduction of representative prochiral alkyl-aryl ketones with a new chiral alkoxy-amine-aluminum derivatives from aluminum hydride and ${\alpha},{\alpha}$-diphenyl-${\beta}$-amino alcohols, such as (S)-(-)-2-amino-3-methyl-1,1-diphenylbutan-1-ol(AMDPB) and (S)-(-)-2-(diphenylhydroxy-methyl)pyrrolidine(DPHMP), in THF at $0^{\circ}C$ was studied. In the reduction of alkoxy-amine-aluminum derivatives, acetophenone, propiophenone, isopropiophenone, and butyrophenone are reduced to corresponding aromatic secoundary alcohols with 34~60 % enantiomeric excess of (S)-isomers. For such ketones, the optical induction was enhanced by increasing a size of alkyl groups.

• Bulletin of the Korean Chemical Society
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• 제22권6호
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• pp.547-548
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• 2001

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.231.2-232
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• 2002

The synthesis of chiral 1,2-amino alcohols has been an area of intense study in the synthetic and industrial fields, because of their important roles in organic synthesis as fundamental building blocks and their occurrence in a number of natural products. drugs. and chiral auxiliaries or ligands. General methods for the synthesis of these compounds can be divided into two large categories: functional group transformations and the C-C or the C-N bond formations. (omitted)

• 대한화학회지
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• 제39권2호
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• pp.94-102
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• 1995

모세관 기체크로마토그래피에 의한 cyclodextrin 정지상들(PH-${\beta}$-CD, DA-${\beta}$-CD, TA-${\gamma}$-CD)을 이용하여 라세미 알코올들과 그 유도체들의 분리를 연구하였다. 실험에 사용한 모든 알코올들은 trifluoro acetic anhydride, acetic anhydride, trichloro acetic anhydride를 써서 유도화하였다. 거울상체들의 분리선택성은 acylation 시약의 형태에 상당히 의존하는 것을 알았다. 알코올과 그 유도체들의 광학분활에 대한 최상의 실험조건은 용질분자들의 극성에 따라 다르다. 그리고 키랄분리에 관해서 온도, 컬럼이 극성, 수소 결합력, 알코올과 CD 정지상의 입체효과 등의 의존에 관한 연구를 행하였다. 키랄 인식 기구는 키랄 정지상의 종류에 의존하지 않고, 라세미 알코올의 유도체화에 의존하는 것으로 나타났다.

• 공업화학
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• 제18권6호
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• pp.630-635
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• 2007

구조중에 1개의 tert-부틸기를 가진 새로운 형태의 키랄살렌 착체를 합성하여 비대칭반응 촉매로서 활용하였다. 알루미늄족의 금속염을 소유한 이량체형의 키랄 살렌 촉매는 에폭사이드의 산소고리를 페놀류로 여는 비대칭반응에서 매우 높은 활성과 선택성을 나타내었다. 또한 무기담체에 고정화된 살렌 착체도 이 반응에 대하여 효과적인 촉매로 사용할 수 있었다. 새로운 키랄 살렌촉매 중에 존재하는 금속염의 종류는 광학선택적 반응에서 중요한 영향을 나타내었다.

• Archives of Pharmacal Research
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• 제28권4호
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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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• 제12권6호
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• pp.662-665
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• 1991

In order to prepare new chiral borohydrides (4) possessing chirality on dialkyl moieties, a series of B-alkoxydiisopinocampheylborinates (3) were synthesized by treatment of diisopinocampheylborane ($Ipc_2BH$) with alcohols (R in ROH: Me, Et, i-Pr, t-Bu) and reacted with excess of potassium hydride. Of these chiral borinic esters, only B-methoxydiisopinocampheyl borinate (3a) was converted into the corresponding dialkylmonoalkoxyborohydride (4a). For the other borinic esters, hydride uptake reactions were very slow at room temperature, accompanying disproportionation products at $65^{\circ}C$. The hydride (4a) formed is stable at $0^{\circ}C$ and can be stored over potassium hydride for few months. In the asymmetric reduction of the selected ketones, 4a provided the corresponding alcohols, such as 21% ee for 3-methyl-2-butanone, 11% ee for 2,2-dimethylcyclopentanone, 24% ee for acetophenone, 32% ee for 3-acetylpyridine, 30% for methyl benzoylformate, 31% ee for 4-phenyl-3-butyn-2-one, 39% ee for 3-butyn-2-one, and 34% ee for 3-hexyn-2-one.

• Bulletin of the Korean Chemical Society
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• 제28권9호
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• pp.1553-1561
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• 2007

The new type of heterometallic chiral polymer salen complexes have been synthesized and it has been found that group 13 metal salts (AlCl3, GaCl3 and InCl3) combined to cobalt salen unit played the crucial role in the asymmetric kinetic resolution of racemic epoxides. Polymeric salen catalysts showed very high reactivity and enantioselectivity for the asymmetric ring opening of terminal epoxide with diverse nucleophiles. They provide the enantiopure useful chiral intermediates such as chiral terminal epoxides and α -aryloxy alcohols in one-step process. An efficient methodology for providing very high enantioselectivity can be achieved in the synthesis of valuable chiral building blocks via our catalytic system by combination of various asymmetric ring opening reactions.

• Bulletin of the Korean Chemical Society
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• 제26권7호
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• pp.1101-1103
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• 2005

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2493-2496
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• 2011