• Bulletin of the Korean Chemical Society
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• v.15 no.6
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• pp.448-452
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• 1994

2-Hydroxymethyl-2,5-dihydrothiophene 1,1-dioxide (1) was prepared from thiophene-2-carboxylic acid by consecutive reactions involving the Birch reduction, esterification, reduction with lithium aluminum hydride, and oxidation with Oxone$^{\circledR}$. The esterification of alcohol 1 with various unsaturated carboxylic acids provided the precursors 8 for the intramolecular Diels-Alder reaction. The cheletropic expulsion of sulfur dioxide from the esters 8 followed by intramolecular Diels-Alder reaction furnished bicyclic ${\gamma}$-and ${\delta}$-lactones.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1208-1254
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• 2002

Photoreaction of N-(o-halophenyl)acetamide in basic acetonitrile produces an intramolecular substituted product, 2-methylbenzoxazole in addition to reduced product, acetanilide, whereas photoreaction of N-(o-halobenzyl) acetamide affords a reduced product, N-benzylacetamide only. On the basis of preparative reaction, kinetics, and UV/vis absorption behavior, an electrophilic aromatic substitution of aryl halide with oxygen of its amide bond are proposed.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2527-2530
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• 2010

The stereoselectivity of the intramolecular Diels-Alder reactions of 1 and its derivatives were investigated by ab initio calculations. The stereoselectivity mainly originates from the steric repulsion and the orbital interactions. The additional s-cis and s-trans conformations by introducing the carbonyl group at the neighbor of diene or dienophile may change the stereoselectivity, hence this kind of substitution can be utilized for stereoselectivive asymmetric synthesis.

• Archives of Pharmacal Research
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• v.29 no.6
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• pp.476-478
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• 2006

In order to construct a benzofuran library, we developed a model study of benzbromarone. Synthesis has been achieved in 53% overall yield, starting from phenol via the key intermediate 2-ethylbenzofuran which was afforded by intramolecular Wittig reaction.

• Journal of the Korean Chemical Society
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• v.38 no.1
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• pp.61-68
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• 1994

The intramolecular formal iron-catalyzed [4+2] cycloaddition reaction of acetylenic dienes to produce bicyclic products has been investigated. These reactions proceeded, competing via intramolecular carbocyclization and bimolecular cycloaddition. However, the iron-catalyzed bicyclic carbocyclization of 4,4-dimethyl-3-(tert-butyldimethylsiloxy)-1-phenyl-6,8-decadien-1-yne(11) yielded exclusively bicyclic diene product(yield 78.1%). From this result, we found that the substrate containing a dimethyl substitutent at the 4,4-position helped to promote the intramolecular reaction, which is stable to the iron catalyzed conditions.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.289-290
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• 2009

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.927-930
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• 2004

• Journal of the Korean Chemical Society
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• v.66 no.1
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• pp.9-14
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• 2022

An efficient method for the synthesis of 1-aminophthalans has been developed. The intramolecular oxa-Mannich reaction of 1,3-dihydro-2-benzofuran-1-ols with p-toluenesulfonylamine in the presence of Cs₂CO₃ as a base, without using any catalyst, provided the desired 1-aminophthalans in moderate to good yields.

• Journal of Life Science
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• v.5 no.4
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• pp.155-161
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• 1995

The effects of substrate concentration, enzyme concentration, reaction temperature, and water content were investigated in intramolecular esterification. This study used cyclohexane as organic solvent, power lipase as enzyme, and benzyl alcohol and octanoic acid as substrate. The initial reaction rate was found to be proportional to enzyme concentration; followed Michaelis-Menten equation for octanoic acid; and was inhibited by benzyl alcohol . The observed initial reaction rate first increased, then decreased with increasing reaction temperature, giving rise to the maximum rate at 20$\circ$. The drop in the reaction rate at higher temperature was to partition equilibrium change of substrate between organic solvent and hydration layer of enzyme molecule in addition to the deactivation by enzyme denaturation. Water layer surrounding enzyme molecule seemed to activate in organic solvent and the realistic reaction was done in the water layer. In the enzymatic reaction in organic solvent, the initial reaction rate was influenced by partition quilibrium of substrate, so the optimum condition of substrate concentration, enzyme concentration, reaction temperature, and water content would give a good design tool.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2351-2356
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• 2010

Various dienamide derivatives were synthesized in reasonable yields from benzonitriles having an amide moiety at the ortho-position, via the sequential (i) In-mediated allylation of nitrile moiety to form an imine intermediate, (ii) intramolecular quenching of an acyl group by the imine intermediate, and (iii) a proton transfer to dienamide.