• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2289-2292
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• 2010

Long chain dicationic ammonium salts were used successfully as phase transfer catalyst in the condensation reactions of aromatic aldehydes in water under ultrasonic irradiation for the first time. The quaternary salt having longer distance between the cation centers was more effective than the mono- and dicationic ones having short chain.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.662-665
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• 2011

Highly efficient, three-component condensation of aromatic aldehyde, malononitrile and 4-hydroxycoumarin promoted by neat silica gel at room temperature is described. The method offers an excellent alternative to the synthesis of 3,4-dihydropyrano[c]chromenes. The reactions are fast and clean, and the products are obtained with good yield and purity.

• Journal of ILASS-Korea
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• v.20 no.2
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• pp.121-129
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• 2015

This study was designed to investigate the emission characteristics of unregulated pollutants (Aldehyde, VOCs, PAHs) as well as regulated pollutants (CO, HC, NOx and PM) from diesel medium-duty trucks. The emission characteristics of unregulated and regulated pollutants were assessed based on regulation standards (EURO 4 and EURO 5) and intake weight (2.5 ton and 5 ton). The results show that unregulated and regulated pollutants remained almost unchanged at higher speeds but decreased at below 23.5 km/h. Reduction in unregulated and regulated pollutants was noticeable in vehicles of recent regulation standards and light intake weight. The analysis of aldehyde using UPLC showed that formaldehyde and acetaldehyde of aldehyde were most dominant. The GC/MS analysis showed that benzene, toluene, ethylbenzene and xylene of VOCs was over 80% followed by toluene, xylene, ethylbenzene and benzene. In addition, the analysis of PAHs using GC/TOF-MS indicated that bi- and tricyclic aromatic ring of aromatic compounds was 73% and 53% at 2.5 ton and 5 ton vehicles, respectively. The results of this study will be contributed to establish HAPs inventory.

• Bulletin of the Korean Chemical Society
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• v.27 no.1
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• pp.121-122
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• 2006

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.672-677
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• 1996

Volatile flavour components rates from aromatic rices were analyzed by Electronic nose systems. In functional group, polar compounds and aldehyde compounds showed much of volatile flavour components than apolar compounds, sulphur compounds and aminated compounds. The profiles of volatile flavour components rates were markedly differents of sen-sing times, amylose content.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1203-1205
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• 2006

During the synthesis of 4-fluorobenzaldehyde via the SNAr reaction of 4-nitrobenzaldehyde with TBAF, it was found that an equivalent amount of TBAF could oxidize benzaldehyde to benzoic acid. The reaction of 4-nitrobenzaldehyde with tetrabutylammonium fluoride (TBAF) gave 4-nitrobenzoic acid in high yield. Depending on the reaction conditions, other aromatic aldehydes produced acids with fewer amounts of alcohols. However, this type of oxidation has limited practical applications. Nevertheless, the mechanism is quite different from the Cannizzaro reaction because the amounts of the acid salt and alcohol formed were different.

• Journal of the Korean Chemical Society
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• v.58 no.4
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• pp.377-380
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• 2014

A noval derivatives of 3-substituted[1,2,4]triazolo[4,3-b]pyridazine (4a-4o) and 7,8,9,10-tetrahydrobenzo[4,5] thieno[2,3-d][1,2,4]triazolo[4,3-b]pyridazine (7a-7l) is prepared by the reaction of heteroaryl hydrazone from the aldehyde and pyridazinohydrazine derivative, followed by subjecting the intermediate directly to oxidative cyclization employing the mixture of $Me_4NBr$ and Oxone. These derivatives were subjected to preliminary antimicrobial activities against microorganism. All these compounds exhibit good to moderate activity.

• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.606-611
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• 2013

A facile one-pot syhthesis of 3-substituted triazolopyridazine and thieno-triazolopyridazine derivatives is described. This protocol involves the preparation of heteroaryl hydrazone from the aldehyde and pyridazinohydrazine derivative followed by subjecting the intermediate directly to oxidative cyclization to assemble the desired 1,2,4-triazloe moiety by employing the mixture of Me4NBr and oxone. This condition is efficient and is able to tolerate wide range of functional groups.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2555-2558
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• 2009

The condensation of cyclic ketone with aromatic aldehydes in the presence of ammonium acetate under ethanol media affords the corresponding 5-aryl-7,8,13,14-tetrahydrodibenzo[a,i]phenanthridine with excellent yield. This mild and efficient procedure with high yield is also applied to the synthesis of 2,4-diaryl-6,7-benzo-3-azabicyclo- [3.3.1]nonan-9-ones and ${\alpha},{\alpha}{$’-bis(substituted benzylidene)cycloalkanones.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.426-430
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• 2003

A range of methine dyes has been synthesized by condensation of highly electronegative active methylene compound dicyanomethylenecyclopentane derived from cyclopentanone with the formyl group of substituted benzaldehydes. The electronic absorption spectroscopic properties of the dyes were investigated. In general, substituents on the aromatic aldehyde moiety have a significant effect on the visible absorption maxima of the dyes; increasing the solvent polarity also showed a pronounced effect on the absorption maxima.