• 통합자연과학논문집
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• 제8권2호
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• pp.107-110
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• 2015

Amino acid-catalyzed directed asymmetric aldol reactions showed enhanced enantioselectivity when conducted in ionic liquids. Optically active products were afforded in better yields (up to 23% higher) and enantiomeric excess (up to 21% higher) in ionic liquids than in conventional organic solvents.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2465-2468
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• 2011

• Bulletin of the Korean Chemical Society
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• 제25권1호
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• pp.143-146
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• 2004

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.327-333
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• 2009

For the Pt-catalyzed nucleophilic addition of enones, Pt complexes were employed in the presence of various phosphine ligands and $H_2\;(or\;Et_3SiH),$ affording inter- and intra-molecular coupling products in good to modest yield. Depending on reaction protocols, different phosphine ligands were required to optimize the conditions. In the aldol reaction, the Pt catalyst involving $P(2,4,6-(OMe)_3C_6H_2)3\;or\;P(p-OMeC_6H_4)_3$ was chosen. Michael reaction proceeds in good yields in the presence of $P(p-CF_3C_6H_4)_3$. Regarding the activity of the reductants, $H_2$ exhibited superior activity to $Et_3SiH$, resulting in a shorter reaction time and higher yield in the aldol and Michael reaction. In light of the deuterium labeling studies, the catalytic cycle including the hydrometalation of the enones by the platinum hydride species was proposed.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1677-1681
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• 2005

Aldol condensation of 2-acetylthiophene, 2-acetylpyrrole and 2-acetylpyridine with different aromatic aldehydes were carried out in water in heterogeneous phases in the presence of cetyltrimethylammonium bromide as cationic surfactant at room temperature. All the reactions occur in a short time with excellent yields of steroselective hetarylpropanones in water as environmental friendly solvent.

• 대한화학회지
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• 제33권4호
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• pp.426-430
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• 1989

아미노 알콜에서 합성한 티아졸리딘치온 [4-(S)-IPTT, 4(S)-ETT]은 주석을 매개체로한 알돌 축합반응의 키랄 보조제로 이용되었다. Stannous triflate와 3-아세틸티아졸리딘-2-티온을 반응시켜 얻은 2가주석 엔올레이트를 어키랄 알데히드와 반응시켜 ${\beta}$-하이드록시 카르보닐 화합물을 입체선택적으로 얻었다. 이러한 키랄 보조제는 가메탄올 분해반응으로 쉽게 에스터화 되기 때문에 절대구조 동정을 용이하게 하는 장점도 있었다.

• 대한화학회지
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• 제57권2호
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• pp.252-259
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• 2013

A green and simple method to synthesize of 1,4-diketones via aldol reaction of arylglyoxals and ketones such as 1-(4-methoxyphenyl)-2-propanone, deoxybenzoin and substituted acetophenones in the presence of a catalytic amount of DABCO in water at room temperature has been reported. Corresponding 2-hydroxy-1,4-diones were obtained in moderate to high yields with simple separation of obtained solid from reaction mixture and recrystallization.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.797-802
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• 2009

Potential of acetates and related compounds in glacial acetic acid as a catalyst for aldol-type condensation reactions was examined. Reactions of cycloalkanones or selected heteroaromatics with aldehydes in presence of 10 mol% of various acetates in acetic acid afforded ${\alpha},{\alpha}$'-bis(substituted-benzylidene)cycloalkanones and substituted-benzylidene-mackinazolinones, respectively, in good yields. Among the compounds tested, ammonium acetate is the best and effective especially towards the reactions of mackinazolinone and aliphatic aldehydes to afford 6-alkylidenemackinazolinones.

• 대한화학회지
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• 제57권5호
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• pp.591-598
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• 2013

A series of chiral prolinamide compounds with pyridine-2, 6-dicarboxylic acid moieties derived from L-proline have been designed and synthesized, their catalytic properties for direct asymmetric aldol reactions were also studied in this article. These catalysts gave the aldol product in high yield (87%) and high enantioselectivity, up to 85%, of the anti-structure at room temperature but gave disappointing results at a lower temperature or when additive was added. Conditions, including solvents, temperature and additives were screened for the reactions. Moreover, the influence of presence of water on yield and stereoselectivity was also discussed.

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.736-740
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• 2002

An efficient and practical synthetic method of △1 -3-octalone, which is a versatile building block for thesyntheses of polycyclic compounds, has been developed. The dianion of ethyl acetoacetate reacts with cyclohexene-1-carboxaldehyde (3) to produce the aldol adduct 6, which then undergoes Mn(Ⅲ)-mediated radical cyclization followed by acetate elimination to give △1 -3-octalone 4. A detailed mechanistic insight of Mn(Ⅲ)-mediated cyclization of 6 has been disclosed.