• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1195-1200
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• 2011

The catalytic enantioselective Mannich-type reaction promoted by chiral binaphthyl-modified bifunctional organocatalysts is described. The treatment of ${\alpha}$-fluoro-${\beta}$-ketoesters with N-Boc imines under mild reaction conditions afforded the corresponding ${\beta}$-aminated ${\alpha}$-fluoro-${\beta}$-ketoesters with excellent enantioselectivities (up to 98% ee).

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.829-836
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• 2009

The catalytic enantioselective electrophilic fluorinations of active methine compounds promoted chiral palladium complexes have been developed. Treatment of $\beta$-keto phosphonates and $\beta$-ketoesters with N-fluorobenzenesulfonimide as the fluorine source under mild reaction conditions afforded the corresponding $\alpha$-fluorinated adducts in high yields with excellent enantiomeric excesses (up to 99% ee). These reactions can be conducted in alcoholic solvents without any precaution to exclude water and moisture.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1441-1442
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• 2009

• 대한화학회지
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• 제55권4호
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• pp.638-643
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• 2011

Silica sulfuric acid (SSA)를 이용하여 ethylenediamine (EDA)과 o-phenylenediamine (o-PDA)을 2-(4-methylthio benzenesulfonyl)-1,3-dimethyl/1-methyl-3-phenyl/1,3-diphenyl/1-methyl-3-ethoxypropane-1,3-dione 3a-d과의 헤테로고리화 반응을 통하여 좋은 생리활성을 나타내는 1H-1,4-diazepines 4a-d과 3H-1,5-benzodiazepines 5a-d을 좋은 수율로 합성하였다. 이 반응에서 ${\beta}$-diketones/${\beta}$-ketoesters 3a-d는 4-methylthiobenzenesulfonyl chloride 1과 다양한 ${\beta}$-diketones/${\beta}$-ketoesters 2a-d과의 축합반응으로 합성하였으며, 합성한 4a-d와 5a-d 화합물들에 대해서 fantimicrobial, antifungal 및 anthelmintic 활성을 측정하였다.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.249-252
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• 2009

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1759-1762
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• 2014

The enantioselective ${\alpha}$-chlorination of cyclic ${\beta}$-ketoesters catalyzed by chiral 2-aminoalcohol derivatives (2f) has been developed. For the optically active ${\alpha}$-chlorinated products, the isolated yields are in the range of 85-94% and the enantiomeric excesses are up to 84% ee.

• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.878-879
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• 2005

• 대한화학회지
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• 제55권6호
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• pp.1000-1006
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• 2011

A systematic study of Knoevenagel reaction and Nazarov cyclization was made on variety of less reactive carbonyl compounds such as ${\beta}$-ketoesters, 1,3-diketones and cyclic active methylene compounds using $Yb(OTf)_3$ as the catalyst. Recycling study confirms reusability of the catalyst without much loss of activity.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.863-868
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• 2010

Yttrium(III) acetate hydrate-catalyzed novel synthesis of 3,4-dihydropyrimidin-2(1H)-(thio)one derivatives was achieved through one-pot three-component condensation of diversified aldehydes, $\beta$-ketoesters and urea or N-methylurea or thiourea with a molar ratio of 1:1:1.4. In comparison to the classical Biginelli approach, this catalytic method has the advantages of short reaction time and improved product yield.

• 약학회지
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• 제52권6호
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• pp.514-519
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• 2008

We developed a convenient synthetic route to 3-alkylated 2-phenyl-4-quinolone derivatives (4a-h and 5a-c), which were expected to retain antitumor activity. A series of 2,3-dihydro-2-hydroxy-2-phenyl-4-quinolones (3a-h) was synthesized through dehydration, dealcoholation and hydration using acid-catalyzed one-pot reaction from anilines and ethyl benzoylacetates. 3-Methyl (or 3,3-dimethyl)-2-phenyl-4-quinolone derivatives 4 and 5 were synthesized from 3a-h through the methylation using methyl iodide. Formation of quinolone nucleus was undertaken with p-toluenesulfonic acid (p-TSA) at $90{\sim}110^{\circ}C$ in toluene for 3${\sim}$7.5 hr over the Dean-Stark apparatus. The key intermediates in these preparations are ${\beta}$-ketoesters 2a-h, which can be readily obtained from the corresponding anilines 1a-e by reaction with ethyl bezoylacetates.