• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.566-568
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• 2004

• Korean Educational Research Journal
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• v.37 no.1
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• pp.33-45
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• 2016

We propose a research for detection of the fluoride ion using borane compounds. Based on the Lewis acid-base reaction, we discussed the fundamental of sensing for fluoride ion. One of the important aspects in the chemistry of organoboranes is their behaviors as Lewis acids, which is a result of the vacant $2p_{\pi}$ orbital on the tricoordinate boron center. The electronic interaction between boron atoms and ${\pi}$-orbitals of donor molecules, constructed from the carbon 2p orbitals, is generally strong. Boron atoms can reach the desired octet configuration either through ${\pi}$-overlap with a suitable X or through formation of Lewis acid-Lewis base complexes.

• Bulletin of the Korean Chemical Society
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• v.3 no.4
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• pp.149-152
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• 1982

A new convenient method for the reduction of carboxylic acids to the corresponding alcohols via acyloxyborohydrides was explored. Acyloxyborohydrides, prepared from the reaction of various carboxylic acids and sodium borohydride, underwent reduction to the corresponding alcohols readily by the addition of dimethyl sulfate or Lewis acids, such as boron trifluoride etherate and triphenyl borate, presumably through acyloxyboranes. By utilizing this procedure, aliphatic and aromatic acids are rapidly and quantitatively reduced to the corresponding alcohols in terahydrofuran either at room temperature (or at $65^{\circ}$). This procedure provides selective reduction of carboxylic acids in the presence of halogen, nitro, and heterocyclic rings such as furan and thiophene.

• Resources Recycling
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• v.27 no.5
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• pp.3-8
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• 2018

Acid-base reaction together with oxidation-reduction reaction is an important reaction occurring in the aqueous phase. The definition by Lewis on the acid and base is more comprehensive than several definitions. HSAB theory has been introduced to consider the difference in the reactivity among the acids/bases. In this paper, several acid-base reactions were analyzed by applying the definition of acid and base. Moreover, the background of the introduction of HSAB and its application was explained.

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.140-144
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• 1987

The effect of Lewis acids on spectroscopic properties and photodimerization of coumarin and 5,7-dimethoxycoumarin was investigated. Quantum yields of coumarin photodimerization increase in the presence of $BF_3{\cdot}OEt_2$ but those of 5,7-dimethoxycoumarin decrease. The spectroscopic properties of the coumarin-$BF_3{\cdot}OEt_2$ and 5,7-dimethoxycoumarin-$BF_3{\cdot}OEt_2$ complexes were studied by UV, IR, $^1H$ NMR and fluorescence spectroscopy.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1171-1174
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• 2006

Various off-the-shelf Lewis acids in conjunction with various onium salts are screened for coupling reaction of $CO_2$ with epoxides. Among the tested ones, $VCl_3/n-Bu_4NOAc$, $VCl_3/(n-Bu_4NCl$ or PPNCl), $FeCl_3/ n-Bu_4NOAc$, and $FeCl_3/ n-Bu_4NOAc$are proved to be highly active. Propylene oxide, epichlorohydrin, styrene oxide, and cyclohexene oxide can be converted over 90% yields to the corresponding cyclic carbonates without the use of organic solvents under mild conditions by 0.1-1.0 mol% catalyst charge.

• Journal of the Korean Chemical Society
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• v.14 no.3
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• pp.201-206
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• 1970

Furfuryl acetate was chlorinated in presence of acetic acid using carbontetrachloride as the solvent. When the chlorination proceeded at the low concentration of acetic acid, the formation of the tetrachloride was more efficient than that of higher concentration. The chlorination done in presence of various Lewis acids such as aluminum chloride, hydrogen fluoride, and borontrifluoride could not give high yield of tetrachloride, but trichloride. In case of borontrifluoride and hydrogen fluoride, the decomposition of the reaction mixture was apparent. The results were discussed in terms of the stability of furfuryl nucleus towards an electron acceptor and the convenient procedure of preparing trichloro furfuryl acetate was described.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.1887-1890
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• 2010

Cross-linked polystyrene supported aluminium triflate (Ps-Al(OTf)$_3$) was found to be an efficient and chemoselective heterogeneous Lewis acid catalyst for the direct conversion of arenes to sulfones using sulfonic acids as sulfonylating agents. The solid acid catalyst is stable (as a bench top catalyst) and can be easily recovered and reused without appreciable change in its efficiency.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1836-1838
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• 2005

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.150-151
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• 2006

Perfluoroaryl boranes are widely employed as co-catalysts in olefin polymerization processes. Perfluoroaryl diboranes, possessing borane centers in close proximity, are a subclass of this family of compounds that are in theory capable of chelating neutral and anionic bases. The resulting anions are exceptionally weakly coordinating. We have prepared examples of such compounds and studied their coordination behavior with neutral Lewis bases that have the capability to bridge Lewis acid sites in an effort to delineate the kinetic and thermodynamic factors that influence bonding mode. When protic Lewis bases such as alcohols or water are reacted with diboranes, strong Bronsted acids capable of initiating cationic polymerizations under unusual conditions result.