• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1790-1794
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• 2005

Fréchet-type dendritic benzyl azides were efficiently synthesized using 5-(azidomethyl)-1,3-dihydroxybenzene as an azide focal point functionalized unit by adding a generation to the existing dendron and applied for the construction of dendrimers containing 1,2,3-triazole rings as connectors via click chemistry with a tripodal acetylene core.

• Journal of the Korean Chemical Society
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• v.45 no.4
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• pp.318-324
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• 2001

The reaction of 6-chloro-2-hydrazinoquinoxaline(4) or 6-chloro-2-hydrazinoquinoxaline 4-oxide(7) with alkyl (ethoxymethylene)cyanoacetates gave pyrazolylquinoxalines(5, 8). The reaction of compounds 8 with dimethyl acetylenedicarboxylate resulted in the 1,3-dipolar cycloaddition reaction and then ring transformation to afford pyrazolylpyrrolo[1,2-a]quinoxalines(9).

• Bulletin of the Korean Chemical Society
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• v.16 no.11
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• pp.1037-1042
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• 1995

The reaction of acetophenone 1-ureidoethylidenehydrazones 6 with a mixture of triphenylphosphine, carbon tetrachloride, and triethylamine in dichloromethane provides a general route to 1-(1-phenylethenyl)-5-(N-substituted amino)-1,2,4-triazoles 11 via the electrocyclization of the expected azino carbodiimide intermediates 9 to give the resonance stabilized azomethine imine 10a followed by a proton abstraction from the methyl group by amide anion. However, the same reaction of benzaldehyde 1-ureidoethylidenehydrazones 5 was unsuccessful. Under the same conditions, the reactions of benzaldehyde 1-N-acylureidoethylidenehydrazones 7 or acetophenone 1-N-acylureidoethylidenehydrazones 8 afforded 4H-1,2,4-triazolo[1,5-c][1,3,5]oxadiazines 16 or 17 via the zwitterionic species 15, or a [4+2] intramolecular cycloaddition from the carbodiimide intermediates 14, respectively.

• 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.

• Bulletin of the Korean Chemical Society
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• v.19 no.3
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• pp.340-344
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• 1998

A facile synthesis of 4,5-(1',2'-diphenylethylenedithio)-1,3-dithiole-2-thione (dPhEDT-DTT) is carried out via a Diels-Alder type [2+4] cycloaddition reaction of 1,3-dithiol-2,4,5-trithione oligomer and t-stilbene. Molecular structure of dPhEDT-DTT is determined by x-ray crystallography: space group P1, a=11.694(3) Å, b=12.117(3) Å, c=14.688(3) Å, α=113.12(2)°, β=102.23(2)°, γ=107.02(2)°, V= 1699.1(7) Å3, Z=2. It turns out that dPhEDT-DTT crystallizes as a racemic compound consisting of (R,R) and (S,S) enantiomers. Coupling reaction of dPhEDT-DTO undergone in neat P(OEt)3 yields TTF(SEt)4 instead of ET derivative. When PR3 (R=OEt, OPh, Ph) is used in benzene, toluene or xylene, however, dPhEDT-DTO is decomposed.

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.2021-2026
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• 2005

The oxidation of cytidine 1 and inosine 5 by sodium metaperiodate followed by the reaction of the product with $CH_3I$ in NaOH afforded 2',4'-dihydroxyhexopyranosyl derivatives 2 and 14 respectively. The reaction of thiophene-2-carboxylic acid or furfural with cytidine were taken place via cycloaddition afforded adducts 3 and 4 respectivily. The bromination of inosine 5 or its 2',3'-O-isopropylidine inosine 6 led to the formation of 8-bromoanalogue 7 and 8, respectively. The reaction of 8-bromo-2',3'-O-isopropylidine inosine (8) with ethylglycinate hydrochloride afforded 8-ethoxycarbonylmethylaminoinosine 9. The alkylation of the compound 6 with urea led to the formation of 3-carbonylaminoinosine 10. The oxidation of 6 with DCC afforded 4'-formyl derivative 11, which on reaction with ethyl glycinate hydrochloride followed by reaction with sodium cyanoborohydride afforded 12, while the treatment of dialdehyde inosine 13 with ethyl cyanoacetate in the presence of 0.5 N NaOH afforded compound 15.

• Bulletin of the Korean Chemical Society
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• v.4 no.5
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• pp.197-200
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• 1983

The Diels-Alder cycloaddition reactions between dienes and allenic ketones were studied theoretically using CNDO/2 method. It was found that the reaction is a neutral electron demand type with matrix element control and the reactivity, the regio- and stereo-selectivities can be correctly predicted based on interaction energies calculated with the 4-center FMO formalism.

• Rubber Technology
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• v.13 no.1
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• pp.1-9
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• 2012

Click chemistry had enjoyed a wealthy decade after it was introduced by K.B.Sharpless and his co-worker on 2001. Since there is no optimized method for synthesis of click polymer, therefore, this paper introduced three click reaction methods such as catalyst, non-catalyst and azide-end capping for fluorene-based functional click polymers. The obtained polymers have reasonable molecular weight with narrow PDI. The polymers are thermally stable and almost emitted blue light emission. The synthesized fluorene-based functional click polymers were characterized to compare the effect of click reaction methods on polymer electro-optical properties as well as device performance on quasi-solid-state dye sensitized solar cells (DSSCs) applications. The DSSCs with configuration of $SnO_2:F/TiO_2/N719$ dye/quasi-solid-state electrolyte/Pt devices were fabricated using these click polymers as a solid-state electrolyte components. Among the devices, the catalyzed click polymer composed device exhibited a high power conversion efficiency of 4.62% under AM 1.5G illumination ($100mW/cm^2$).These click polymers are promising materials in device application and $Cu^I$-catalyst 1, 3-dipolar cycloaddition click reaction is an efficient synthetic methodology.

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.487-490
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• 1993

A semiempirical methods (PM3-CI-UHF. etc.) for the evaluation of ground and excited state electronic structures of psoralens are applied to angelicin with thymine. The photocycloaddition reaction of angelicin with thymine were deduced to be formed by their preferable HSOMO-LUMO interactions. The photoadduct was inferred to be a C$_{4-}$cycloaddition product with the stereochemistry of cis-anti formed through [2+2] addition reaction between, the 3,4 double bonds of angelicin and the 5,6-double bond of thymine.

• Bulletin of the Korean Chemical Society
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• v.2 no.3
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• pp.112-114
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• 1981

The photocycloaddition reaction of 8-methoxypsoralen with purine and/or pyrimidine bases is studied as a model for the charge transfer interactions of psoralens with DNA bases by the FMO method. The results indicate that, in the case of the molecular complex formation between psoralens and purine and/or pyrimidine bases, the most probable photocycloaddition should occur in the following order: Thy (5,6)<>(3,4) 8-MOP, Cyt(5,6)<>(3,4)8-MOP, Ade (7,8)<>(3,4)8-MOP, Gua(7,8)<>(3,4)8-MOP. The theoretical results for the photocycloaddition reaction are also correlated with the experimental results. The photoadducts between 8-methoxypsoralen and adenine are likely to be C4-cycloadducts through the cycloaddition of 3,4-pyrone double bond of 8-methoxypsoralen to 7,8-double bond of adenine.