• Bulletin of the Korean Chemical Society
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• 제31권8호
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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.

• 대한화학회지
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• 제55권4호
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• pp.662-665
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• 2011

실온에서 방향족 알데히드, 말론니트릴과4-히드록시쿠마린을neat 실리카젤 속에서 one-pot반응시켜서 3,4-dihydropyrano[c]chromenes을 좋은 수율로 합성하였다.

• 한국분무공학회지
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• 제20권2호
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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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• 제27권1호
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• pp.121-122
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• 2006

• 한국작물학회지
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• 제41권6호
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• pp.672-677
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• 1996

전자코를 이용하여 향미품종에 대한 방향성 성분함량비율을 조사한 결과를 요약하면 다음과 같다. 1. 작용기별로는 polar compound계열과 aldehydes compounds계열이 apolar compounds 계열과 sulphur compounds, aminated com-pounds계열에 비해 약 3배정도 높은 함량 비율을 보였다. 2. 백미와 취반상태에 있어서 방향성 성분 함량변화는 대부분 0.02에서 0.1수준으로 증가하는 경향을 보였으나, 찰성을 가진 밀양 14006의 경우는 취반 상태에서 방향성 성분의 함량이 오히려 감소하는 경향을 보였다. 3. 향기와 amylose함량 관계에서는 Japonica와 Indica계열 모두 아밀로스함량이 높을수록 방향성 성분의 함량이 증가하는 경향을 보였다. 4. Headspace 진행 후 센서에 감지되는 시간대는 대부분의 품종에서 30～35초에서 가장 많은 향기성분의 양을 검출할 수 있었으나, 이리 41003의 경우는 방향성성분의 검출이 30초대 이후에 급격히 감소하였다.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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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.

• 대한화학회지
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• 제58권4호
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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.

• 대한화학회지
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• 제57권5호
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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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• 제30권11호
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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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• 제24권4호
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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.