• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.486-489
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• 2011

Potassium dihydrogen phosphate was found to be an efficient catalyst for the Pechmann condensation of phenols with ethyl acetoacetate, leading to the formation of coumarins under microwave-irradiation and solvent-free condition. This procedure offers several advantages, including the low loading of catalysts, high yields, clean reactions, short reaction time for the synthesis of coumarins.

• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.351-354
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• 2010

Nickel nanoparticles (Ni NPs) appeared to exhibit the catalytic activity in one-pot cyclocondensation reaction for the preparation of 3,4-dihydropyrimidine-2(1H)-ones via Biginelli reaction from aromatic/heteroaromatic/aliphatic aldehydes, urea/thiourea and ethyl acetoacetate under microwave irradiation has been described. The UV absorbance spectra showed metallic Ni characteristics and appreciate with the particle size determined by Transmission electron microscopy (TEM). After reaction course the Ni NPs can be re-covered and reused without any apparent loss of activity.

• Journal of the Korean Chemical Society
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• v.58 no.5
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• pp.445-449
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• 2014

A convenient and efficient method has been developed for the one-pot synthesis of dihydropyrimidinones (DHPMs) compounds. Dihydropyrimidinone derivatives were synthesized in good yields using ethyl acetoacetate, aldehyde (aromatic and aliphatic) and urea or thiourea in the presence of ZnO nanoparticles as a catalyst in $H_2O$ as solvent at $80^{\circ}C$. This green chemistry procedure applied to the Biginelli reaction using ZnO nanoparticles as catalyst and illustrated as a rapid preparation of DHPMs in water as solvent. The products were identified by physical data (mp) by comparison with those reported in the literatures.

• Proceedings of the KAIS Fall Conference
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• 2012.05a
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• pp.431-435
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• 2012

Aluminum containing mesoporous molecular sieves Al-SBA-1 ($n_{Si}/n_{Al}$= 2, 5, 10, 15) was synthesized with a one-step method, and the catalyst was characterized with powder X-ray diffraction (XRD), nitrogen adsorption-desorption, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Finally, we studied the catalytic activities of Al-SBA-1 molecular sieves in Pechmann reaction of 3-methoxyphenol and Ethyl acetoacetate to get 7-methoxy-4-methyl coumarin. Four parameters reaction temperature, time, catalyst weight and reactants ratio were optimized.

• YAKHAK HOEJI
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• v.40 no.4
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• pp.382-386
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• 1996

The compound of the 6,7-dichloroquinoline-5,8-dione has two asymmetric chloro radicals at the position of the C6 and C7. When the compound reacts with ethyl acetoacetate in the presence of sodium ethoxide, it is considered that C6 and/or C7 position of the compound can be substitued. The exact substitued position of the product (I) could not be identified by the NMR analysis in our experiment. Therefore, we synthesized the 3-ethoxycarbonyl-2-methyl-1-N-propyl pyridino(2,3f)indole-4,9-dione by reaction of the product (I) with propylamine via intramolecular cyclization to identify the substitued position of the product (I) using the X-ray crystallographic structure analysis. The result demonstrates that the position of nucleophilic substitution of the product (I) is at the position of the C6.

• YAKHAK HOEJI
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• v.41 no.5
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• pp.582-587
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• 1997

The 6.7-dichloroquinoline-5,8-dione (I) was reacted with ethyl acetoacetate in the presence of sodium ethoxide to yield 6-(${\alpha}$-acetyl-${\alpha}$-ethoxycarbonyl methyl)-7-chloro-qui noline-5,8-dione(II). When this compound II was reacted with some arylamine (phenyl, p-toluyl, p-fluorophenyl, p-chlorophenyl. p-bromophenyl, p-iodophenyl, p-trifluoromethylphenyl, p-dimethylaminophenyl,indanyl), 1N-aryl-2-methyl-3-ethoxycarbonyl pyridino[2,3-f]-indole-4.9-dione(IIIa-I) were obtained via intramolecular cyclization.

• Journal of the Korean Chemical Society
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• v.53 no.2
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• pp.224-228
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• 2009

• Journal of the Korean Chemical Society
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• v.56 no.3
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• pp.328-333
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• 2012

A simple, convenient and practical green synthetic protocol for sodium bisulfite catalyzed multicomponent reaction of ethyl acetoacetate, hydrazine hydrate, malononitrile, and various aldehydes for the synthesis of 6-amino-4-phenyl-3-methyl-2,4-ihydropyrano[2,3-c]pyrazole-5-carbonitriles using ultrasound irradiations in solvent free condition. This method provides the advantage of operational simplicity, shorter reaction time and excellent yields making the protocol environment friendly and economically lucrative.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2140-2144
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• 2012

A polymer support immobilized acidic ionic liquid was prepared by copolymerization of 3-vinyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate with styrene in the presence of benzoyl peroxide and its primary application as a solid acidic heterogeneous catalyst to the synthesis of Hantzsch 1,4-dihydropyridines through a one-pot three-component reaction of aromatic aldehydes, ethyl acetoacetate and ammonium acetate was investigated. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and a considerable catalytic activity still could be achieved after third run.

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.114-118
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• 2009

A new Zn/O single source precursor, TMEDA-Zn$(eacac)_2$, has been synthesized by using N, N, N’, N’-tetramethylethylendiamine (TMEDA), sodium ethyl-acetoacetate, and $ZnCl_2$. From this organometallic precursor, ZnO thin films have been successfully grown on Si (100) substrates through the metal organic chemical vapor deposition (MOCVD) method at relatively mild conditions in the temperature range of 390~430 ${^{\circ}C}$. The synthesized ZnO films have been found to possess average grain sizes of about 70 nm with an orientation along the c-axis. The precursor and ZnO films are characterized through infrared spectroscopy, nuclear magnetic resonance spectroscopy, EI-FAB-spectroscopy, elemental analyses, thermal analysis, X-ray diffraction, and field emission scanning electron microscopic analyses.