• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.104-106
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• 1998

3-Aryltetrahydro-1,2-benzisoxazolin-4-one derivatives were prepared by regioselective 1,3-dipolar cycloaddition reactions of various aryl nitrile oxides with 2-cyclohexen-1-one. The structures of these compounds were designed as a modifications of triketone herbicides and showed good herbicidal activity.

• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1194-1201
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• 2004

Michael addition of certain nucleophiles on ${\alpha}$ , ${\beta}$-unsaturated ketones 1 led to the formation of adducts 2-7 as well as the reaction of arylidene derivatives with secondary amines afforded the amino compounds 9 and 11. Also, dialkylmalonates were treated with ${\alpha}$-cyano cinnamide to afford 13. On the other hand, double Michael cycloaddition of ethylcyanoacetate or tetrachlorophthalic anhydride to the suitable divinylketone were synthesized to produce 15-17. Selected compounds (13 and 6) were screened for muscle relaxant, anticonvulsant, and sedative activities using established pharmacological models. Their activities were compared with that of phenobarbital sodium taken as standard. Compound 6 was the most potent muscle relaxant while compounds 13a and 13c offered the highest anticonvulsant activity. Meanwhile compound 13c showed the highest potentiation of phenobarbital induced sleep in mice.

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.302-306
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• 1999

The 1,3-dipolar cycloaddition reaction of the quinoxaline 4-oxide 10 with 2-chloroacrylonitrile gave the 2,3-dihydro-lH-1,2-diazepino[3,4-blquinoxalines lla, b, respectively, which were converted into the 2,3,4,6-tetrahydro-lH-l,2-diazepino[3,4-b]quinoxaline 12. The reaction of compound lla with selenium dioxide in acetic acid/water resulted in ring transformation to give the 1,4-dihydro-4-oxopyridazino[3,4-blquinoxaline 13.

• Journal of the Korean Chemical Society
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• v.14 no.3
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• pp.271-275
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• 1970

The effect of dimethyl maleate on the rate of thermolysis of 3,4,5,6-Tetrachlorobenzene-2-Diazo-1-Oxide in 1-chloronaphthalene at $130.2^{\circ}$ was investigated: In a separate experiment, the effect of dimethyl fumarate upon the same reaction at the same temperature was investigated. The rate of thermolysis was decreased by dimethyl maleate, while dimethyl fumarate accelerated the reaction. Some kinetic parameters of the thermolysis of 3,4,5,6-Tetrachlorobenzene-2-Diazo-1-Oxide were calculated. A mechanism of isomerization of dimethyl maleate to dimethyl fumarate by 3,4,5,6-Tetrachlorobenzene-2-Diazo-1-Oxide was proposed.

• Journal of the Korean Chemical Society
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• v.13 no.1
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• pp.75-82
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• 1969

4-Ethyltropolone has been prepared in three steps from cyclopentadiene by a dichloroketene process, and at the same time, a comparison has also been made with the case of tropolone synthesis. In the addition reaction of dichloroketene to cyclopentadiene as well as to ethylcyclopentadiene, and also in the separation of cycloadducts from reaction mixture, the best results were given by prevention of the reactants from dimerization. Under these condition, the yields of cycloadducts were around 70% for both. Tropolone and 4-ethyltropolone were obtained in the yield of 51% and 32%, respectively, by hydrolysis of cycloadducts with potassium acetate in aqueous acetic acid. These results revealed that the steric effect of ethylgroup was more sensitive to the hydrolysis than to the cycloaddition reaction. A comparison of UV, IR and NMR spectroscopic results of 4-ethyltropolone with those of tropolone was also made together with a brief discussion of the tropolone ring system and ethylgroup effect.

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.157-162
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• 2009

General, fast, and efficient methods for the synthesis of Fréchet-type dendrimers having core diversities were elaborated. Two core building blocks, 4,4'-(3,5-bis(propargyloxy)benzyloxy)bisphenyl and N,N,N',N'-tetra(prop-2- ynyloxycarbonylethyl)-1,2-diaminoethane, were designed to serve as the alkyne functionalities for dendrimer growth via click reactions with the azide-dendrons. The synthetic strategy involved an 1,3-dipolar cycloaddition reaction between an alkyne and an azide- functionalized Fréchet-type dendrons in the presence of Cu(I) species which is known as the best example of click chemistry.

• Bulletin of the Korean Chemical Society
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• v.26 no.10
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• pp.1597-1599
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• 2005

• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1795-1800
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• 2006

The convergent synthesis of symmetric PAMAM-like dendrimers from azide-functionalized poly(amido- amine) (PAMAM) dendrons and two different multi-alkynes was investigated. The stitching method was based on the click chemistry protocol, i.e., the copper-catalyzed cycloaddition reaction between an alkyne and an azide.

• Journal of the Korean Magnetic Resonance Society
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• v.8 no.1
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• pp.62-69
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• 2004

Bicyclolactones obtained from the Diels-Alder cycloaddition of 3,5-dibromo-2-pyrone can undergo various palladium catalyzed cross coupling reactions to afford aryl bicyclolactones. The resulting coupled products can be readily converted into various 3-OH cyclohexenes via lactone ring openings, while those bearing dienyl units underwent highly diastereoselective Diels-Alder cycloadditions with selected dienophiles to funish multiply functionalized polycarbocycles. Bromo-bicyclic diene furnished two different diastereomers endo-form (62%) and exo-form (38%) upon cycloadditions with N-Et maleimide (NEM), and their stereochemistries were identified with NMR.

• Macromolecular Research
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• v.9 no.6
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• pp.339-344
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• 2001

In order to investigate the photoalignment mechanism of nematic liquid crystals on a polymer film, a new photoreactive polymer having chalcone groups as side chains was synthesized. Linearly polarized UV light causes preferential photoreactions of the chalcone unit along the polarization direction and thus induces the anisotrpy in the polymer alignment layer resulting in homogeneous LC alignment perpendicular to the polarization direction. The sequential investigations of photoalignment generated by the preferential E/Z isomerization and (2+2) cycloaddition reactions show that either photoreaction can solely induce the LC alignment in the direction perpendicular to UV polarization.