• Bulletin of the Korean Chemical Society
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• v.16 no.9
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• pp.859-863
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• 1995

The prostaglandin analogue 12-epi-PGF2α (2) has been synthesized from optically active cis-4-t-butyldimethylsilyloxy-2-cyclopenten-1-ol (4b) in 4 steps in an overall yield of 21%. An extremely efficient Pd(Ⅱ)-mediated, three-component coupling reaction is employed to obtain the key intermediate 9.

• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.369-374
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• 2006

$Rh-Pt/Al_{2}O_{3}$ catalysts were used for the first time to study its reaction characteristics in the asymmetric hydrogenation of ethyl pyruvate. The catalysts were prepared either by impregnation of Rh on a commercial $Pt/Al_{2}O_{3}$ or by sequential impregnation of Rh followed by impregnation of Pt on $Al_{2}O_{3}$. Reaction rate and enantiomeric excess (ee%) were compared according to the preparation method, Rh contents, and the reduction temperature of the catalyst. The physical characteristics of the catalysts were analyzed using XRD and TEM. Bimetallic $Rh-Pt/Al_{2}O_{3}$ catalysts showed an improved reaction rate and optical purity (63.6 ee%) with increasing the reduction temperature. The variation of the Rh contents as well as the preparation method elicited a big difference on the reaction rate, while enantiomeric excess (ee%) was lower (56~60%) with all bimetallic catalysts than with monometallic $Pt/Al_{2}O_{3}$ catalyst.

• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.694-696
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• 2010

• Journal of Integrative Natural Science
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• v.8 no.2
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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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• v.35 no.1
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• pp.98-102
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• 2014

The organocatalytic enantioselective Michael addition reaction promoted by chiral binaphthyl-modified squaramide catalyst have been developed, allowing facile synthesis of the corresponding chiral 2-amino-4H-chromenes derivatives with excellent enantioselectivity (up to 99% ee). The method reported represents a practical entry for the preparation of chiral 2-amino-4H-chromenes derivatives.

• Journal of the Korean Chemical Society
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• v.60 no.1
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• pp.21-27
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• 2016

Novel push-pull chromophores containing 5’-(4-(bis(9,9-dimethyl-9H-fluoren-2-yl)aniline (bisDMFA) as a donor and phenylazo-methylpyrrolyl-boron difluoride (PhAPy-BF₂) as an acceptor were designed and synthesized by the Knoevenagel condensation reaction for organic solar cells. Various electron withdrawing moieties were effectively introduced using 2,4-dimethyl-1H-pyrrole to afford new asymmetric BF₂-azopyrrole molecules that were characterized by UV-vis spectroscopy and cyclic voltammetry measurements.

• Archives of Pharmacal Research
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• v.5 no.2
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• pp.93-96
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• 1982

By using recemic 3-bromo-5-isobutyl-5-methylhydantoin (3a') in dry N, N-dimethylformamide which is a model reagent for asymmetric bromolactonization, bromolactonization of a series of olefinic acids was carried out to furnish corresponding bromolactones in moderate yields.

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.129-141
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• 2005

(-)-Fumagillol (1), a hydrolysis product of fumagillin, has been synthesized by several group from commercially available 1,2:5,6-di-O-isopropylidene-${\alpha}$-D-allofuranose in a highly stereoselective manner. Chiral centers on C5 and C6 came from D-allofuranose and the asymmetric center on C4 was accomplished by 1,3-chirality transfer using the Claisen rearrangement on a chiral allyl alcohol. Chirality, which is necessary on an epoxide consisting of the spiro-ring system, was diastereoselectively constructed by the well-known reaction, intramolecular ester enolate alkylation (IEEA), which showed that this reaction can be applied to the alpha-alkoxy ester system. The epoxide on the side chain was regioselectively introduced by the difference between the number of substituents on the vinyl groups. This accomplishment proved that IEEA can be a useful tool for the synthesis of complex molecules.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1439-1440
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• 2009

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.471-473
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• 1997