• Bulletin of the Korean Chemical Society
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• 제28권2호
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• pp.281-284
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• 2007

Neopentyl arenesulfonates react with secondary alkylmagnesium chlorides in the presence of dppfNiCl2 to produce the corresponding arenes via the reductive cleavage of carbon-sulfur bond. Highest yield is obtained by using three equivalents of Grignard reagent to a mixture of arenesulfonate and dppfNiCl2 in Et2O at room temperature. This reaction represents a novel method allowing the efficient hydrogenolysis of sulfur-containing groups in aromatic compounds.

• 한국식품영양과학회지
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• 제20권3호
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• pp.220-224
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• 1991

물 및 다섯가지 탈검제(citric acid, phosphoric acid, acetic anhydride 및 maleic anhydride)를 사용하여 미강유를 탈검하고 그 탈검효율을 비교하였다. 미강유 원유로부터 인 함유 물질을 제거하는데 있어서 모든 탈검제가 보다 효과적이었으며, 특히 acetic anhydride와 phosphoric acid는 각각 92.5% 및 93.3%까지 인 함유율을 저하시켰다. 또한 비수화성 인지질 특히 Lyso PC를 제거하는데 있어서 모든 탈검제가 효과적이었다. 미강유로부터 추출한 AI의 인지질은 주로 PC, PI, PE 및 Lyso PC로 구성되어 있었으며, 주요 지방산은 oleic acid, linoleic acid 및 palmitic acid의 순이었다. Acetic anhydride를 사용하여 얻은 AI가 가장 안정된 유화를 형성하였으며, 반면에 phosphoric acid 및 oxalic acid를 처리하여 얻은 AI는 매우 빈약한 유화성을 나타냈다.

• 대한화학회지
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• 제42권2호
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• pp.228-231
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• 1998

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.280-282
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• 2014

• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.695-697
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• 2007

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.341-343
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• 2011

• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.237-240
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• 2001

• Mass Spectrometry Letters
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• 제13권3호
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• pp.49-57
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• 2022

During electrospray ionization mass spectrometry (ESI-MS) analysis of proteins, the addition of supercharging agents allows for adjusting the maximal charge state, affecting the charge state distribution, and increases the number of ions reaching the detector thus, improving signal detection. We postulate that in di-substituted arene isomers, molecules with higher polarizability values should generate greater interactions and hence elicit higher signal intensities. Polarizability is an electronic parameter which has been demonstrated to predict many chemical interactions. Many properties can be predicted based on charge polarization. Molecular polarizability is a vital descriptor for explaining intermolecular interactions. We employed DFT (density functional/Hartree-Fock hybrid model, B3LYP)-derived descriptors and computed molecular polarizability for ten disubstituted arene reagents, each set made up of three (ortho, meta, para) isomers, with reported use as supercharging reagents during ESI experiments. The atomic electronic inputs were ionization potential (IP), electron affinity (EA), electronegativity (𝛘), hardness (η), chemical potential (µ), and dipole moment (D). We determined that the para isomers showed the highest polarizability values in nine of the ten sets. There was no difference between the ortho and meta isomers. Polarizability also increased with increasing complexity of the substituents on the benzene ring. Polarizability correlated positively with IP, EA, 𝛘, η, and D but correlated negatively with chemical potential. This DFT study predicts that the para isomers of di-substituted arene isomers should elicit the strongest ESI responses. An experimental comparison of the three isomers, especially of larger supercharging molecules, could be carried out to establish this premise.

• Bulletin of the Korean Chemical Society
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• 제27권4호
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• pp.463-472
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• 2006

The preparation of enatiomerically enriched homoallylic alcohols through asymmetric addition of chiral allylic transfer reagents and allylating reagents with chiral catalysts to the carbonyl functionalities represents an important chemical transformation. Excellent progress has been made over past decade in the development and application of catalytic asymmetric allylic transfer reactions. In this account, our efforts for the various intermolecular allylic transfer reactions such as allylation, propargylation, allenylation, and dienylation utilizing accelerating strategy and sequential allylic transfer reactions to achieve multiple stereoselection mainly using transition metal catalysts are described.

• Membrane and Water Treatment
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• 제14권4호
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• pp.181-189
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• 2023

The Covid-19 pandemic has increased demand for chlorine-based sanitizing solutions, most of which contain hypochlorous acid (HOCl) as an active agent. Free chlorine (HOCl) in these sanitizers is crucial for their efficacy. Disposable test strips are affordable and convenient tools for determining various qualitative and quantitative parameters. In this study, disposable opto-chemical test strips were developed by physically immobilizing 3,3',5,5'-tetramethylbenzidine (TMB) and o-dianisidine (o-D) reagents on chromatography and filter paper-based test strips for the visualization and detection of free chlorine in the form of HOCl. The reagents undergo a rapid color change upon reaction with chlorine through a redox reaction. The paper-based test strips showed rapid color change within a minute and a low sample volume requirement (1 ml). This portable, disposable paper-based test strip is a simple and cost-effective way to rapidly detect the presence of HOCl sanitizers for home and field applications. Both TMB and o-D successfully detected chlorine. Chromatography paper proved to be the more efficient option among the two papers used as substrates for the reagents (TMB and o-D). It exhibited high retention capacity and high performance in terms of color transformation when reacting with HOCl, even after two months of storage.