• Bulletin of the Korean Chemical Society
• /
• v.30 no.11
• /
• pp.2833-2836
• /
• 2009

• Bulletin of the Korean Chemical Society
• /
• v.25 no.11
• /
• pp.1726-1728
• /
• 2004

• Bulletin of the Korean Chemical Society
• /
• v.32 no.2
• /
• pp.656-658
• /
• 2011

A green and efficient method for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones and -thiones through one-pot three-component reaction of ethyl acetoacetate, an aryl aldehyde, and urea or thiourea in acetonitrile using silica gel-supported polyphosphoric acid (PPA-$SiO_2$) as catalyst is described. Compared to the classical Biginelli reaction conditions, the present methodology offers several advantages such as high yields, relatively short reaction times, mild reaction condition and a recyclable catalyst with a very easy work up.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.4
• /
• pp.994-1000
• /
• 2014

Synthesis of tetrahydroimidazo[1,2-a]pyridines and tetrahydropyrido[1,2-a] pyrimidines by a one-pot and three component reaction of ${\alpha}$-oxoketenedithioacetals, diamines and DMAD in water has been described. Different routes for accessing the desired compounds were examined and a few specially designed-substrates have been utilized further to afford the new imidazo and pyrido fused [1,8] naphthyridine tetracyclic compound by $S_NAr$ intramolecular cyclization.

• Journal of Soil and Groundwater Environment
• /
• v.25 no.1
• /
• pp.95-105
• /
• 2020

In this study, iron nanoparticles impregnated hydrochar (FeNPs@HC) was synthesized using lignocellulosic waste and simple one-pot synthetic method. During hydrothermal carbonization (HTC) process, the mixture of lignocellulosic waste and ferric nitrate (0.1~0.5 M) as a precursor of iron nanoparticles was added and heated to 220℃ for 3 h in a teflon sealed autoclave, followed by calcination at 600℃ in N₂ atmosphere for 1 h. For the characterization of the as-prepared materials, X-ray diffraction (XRD), cation exchange capacity (CEC), fourier transform infrared spectrometer (FT-IR), Brunauer-Emmett-Teller (BET), transmission electron microscope (TEM), Energy Dispersive X-ray Spectroscopy (EDS) were used. The change of Fe(III) concentration in the feedstock influenced characteristics of produced FeNPs@HC and removal efficiency towards As(V) and Pb(II). According to the Langmuir isotherm test, maximum As(V) and Pb(II) adsorption capacity of Fe_0.25NPs@HC were found to be 11.81 and 116.28 mg/g respectively. The results of this study suggest that FeNPs@HC can be potentially used as an adsorbent or soil amendment for remediation of groundwater or soil contaminated with arsenic and cation heavy metals.

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

• Journal of the Korean Chemical Society
• /
• v.60 no.4
• /
• pp.245-250
• /
• 2016

An improved protocol on the synthesis of thiazolo[3,2-a]pyrimidine-6-carboxylate derivatives are reported. Previously, the thiazolo[3,2-a]pyrimidine-6-carboxylate derivatives were prepared in a two-step procedure. Under the improved procedure, the thiazolo[3,2-a]pyrimidine-6-carboxylate derivatives was readily prepared in a one-step reaction. This procedure was found to be more efficient than the previous protocol and also compared to the ultrasound bath and conventional heating methods in terms of yield and reaction time.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.2
• /
• pp.515-518
• /
• 2012

A series of substituted benzimidazoles and benzothiazoles were prepared through the one-pot reaction of ophenylenediamine and o-aminothiophenol with various aldehydes in the presence of ferric hydrogensulfate both in EtOH and water as solvent. The reactions proceed smoothly in excellent yield, high chemoselectivity and with an easy work-up.

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

• Bulletin of the Korean Chemical Society
• /
• v.35 no.10
• /
• pp.2950-2954
• /
• 2014

A series of bis and tris-indolylketones and meridianin alkaloids are prepared by one pot Michael reaction of indole and ketene S,S-acetals under solvent-free condition using mild Lewis acid $InCl_3$.