• Bulletin of the Korean Chemical Society
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• v.31 no.4
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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.

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.361-364
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• 2007

A one-pot Beckmann rearrangement for the preparation of amides from ketones is described using the silica sulfuric acid under Microwave irradiation. Advantages of this method are regioselectivity with high yields in a simple operation and short reaction time, in which the mole ratio of acid and ketone was 1:2 and it should be greener than the currently used systems.

• Journal of the Korean Chemical Society
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• v.51 no.5
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• pp.418-422
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• 2007

A simple and high yielding one-pot method for synthesis of 2,4,5-triarylimidazoles from condensation of benzoin or benzil, ammonium acetate and aromatic aldehydes using sulphanilic acid catalyst is described. The lower priced catalyst, higher yields and shorter reaction time are the advantages of the presented method.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.635-638
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• 2011

A simple and efficient method for the synthesis of $\beta$-amino carbonyl compounds by one-pot three-component Mannich reaction of acetophenone, aromatic aldehydes and aromatic amines using a carbon-based solid acid (CBSA), as an effective and reusable catalyst, is described. The present methodology offers several advantages such as simple procedure with an easy work-up, shorter reaction times, and high yields.

• Bulletin of the Korean Chemical Society
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• v.33 no.9
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• pp.3122-3124
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• 2012

• Applied Chemistry for Engineering
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• v.30 no.1
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• pp.49-53
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• 2019

Hydrous $MnO_2$ nanowires were easily synthesized by an one-pot synthesis with a simple hydrothermal method. As prepared hydrous $MnO_2$ nanowires were characterized with scanning emission microscopy (SEM), transmit emission microscopy (TEM), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET). They showed a good catalytic activity with the suitable nano-size of 4-5 nm and morphology. The furfuryl alcohol was selected as a substrate and the reaction was carried out in a toluene solvent at $100^{\circ}C$ under the atmospheric pressure of oxygen. The hydrous $MnO_2$ nanowire catalyst exhibited an excellent yield of furfural with the first-rate selectivity and conversion. The catalytic performance during recycle tests was also carried out and the catalyst showed a good mechanical strength with a negligible loss in the activity over five reaction cycles.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.644-649
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• 2011

Polyaniline/$SiO_2$ catalyzed one-pot mannich reaction of acetophenone, aromatic aldehydes and aromatic amines are carried out in ethanol to afford various ${\beta}$-amino ketones. The various wt% of polyaniline were supported on pure silica synthesized by using chemical oxidative method. The catalyst prepared has been characterized by means of thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR). Solvent stability of catalyst was tested using UV-Visible spectroscopy. This protocol has several advantages such as high yield, simple work up procedure, non-toxic, clean, easy recovery and reusability of the catalyst.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3963-3966
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• 2011

A series of pyranopyrazoles, was efficiently synthesized via one-pot, four component reaction of ethyl acetoacetate, hydrazine hydrate, aldehydes and malononitrile in the presence of catalytic amount silicotungstic acid under solvent free condition. NOE experiments confirmed that the product exist exclusively in the 2H form. The present protocol offers the advantages of clean reaction, short reaction time, high yield, easy purification and economic availability of the catalyst.

• 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.

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.936-939
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• 2011

Thiamine hydrochloride (VB1) has been used as an acid catalyst in organic synthesis. One pot three component Biginelli condensation of dimedone, urea/thiourea and substituted aromatic aldehydes catalyzed by 10 mol % of thiamine hydrochloride (VB1) in solvent free condition under microwave irradiation in good to excellent yields has been investigated. Utilization of microwave irradiation, simple reaction conditions, short reaction time, ease of product isolation, and purification makes this manipulation very interesting from an economic and environmental perspective.