• Journal of Photoscience
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• v.2 no.2
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• pp.95-98
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• 1995

The photodimers with cyclobutane rings and C$_2$ symmetry, derived from coumarin (syn, head to tail and anti, head to head) have been calculated by PM3-UHF-CI and Molecular Mechanics force field. The photocycloaddition to coumarin and 5,7-dimethoxycoumarin(DMC) dimers were deduced to be formed by their preferable frontier orbital interactions and via more stable cycloaddition by the C$_3$, C$_4$ bond. These results are consistent with the coumarin dimer model that the theoretical C$_4$-photocyclodimer of coumarin is predicted much more than the experimental C$_4$-photocyclodimer.

• Journal of Photoscience
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• v.2 no.2
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• pp.99-101
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• 1995

A semiempirical methods(PM3-CI-UHF, MM2) for the evaluation of ground and excited state electronic structures of electron-donating substituents are applied to 4, 5', 8-trimethylpsoralen(TMP) with TMP dimer. Three types of product have been proposed; (1) pyrone< >pyrone, (2) pyrone< >furan, (3) hetero dimer resulting from the C$_4$-cycloaddition between the furan end of one TMP moiety and the pyrone end of the other, with cis-syn configuration.

• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.727-730
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• 2010

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1400-1402
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• 2010

• Journal of the Korean Chemical Society
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• v.59 no.3
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• pp.205-208
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• 2015

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2703-2706
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• 2012

New C60 fullerenes derivatives [G1]-C60 (1) and [G2]-C60 (2) comprising of phenylenevinylene bridges and phenylquinoline peripheral surface groups were synthesized by 1,3-dipolar cycloaddition reaction of fullerene C60 with azomethine ylide in situ generated from [Gx]-CHO dendrons (x = 1 and 2) and sarcosine.

• Journal of the Korean Chemical Society
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• v.39 no.10
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• pp.830-833
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• 1995

• Bulletin of the Korean Chemical Society
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• v.28 no.7
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• pp.1089-1090
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• 2007

• Journal of the Korean Chemical Society
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• v.16 no.3
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• pp.178-188
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• 1972

Diethyl itaconate was found to react tetrafluoroethylene, trifluorochloroethylene, and 1,1-difluoro-2,2-dichloroethylene quite rendily at $180^{\circ}C$ to form 1-carboxy-2,2,3,3,-tetrahalo-cyclobutane ethanoic acid derivatives ${C{\underline{X_2-CF_2-CH_2-}}C-(COOEt)-CH_2COOEt$, where X is Cl or F). Diethylcitraconate failed to yeild any cycloaddition products. The Physical and Chemical properties of the above esters and their dericatives are characterized and compared with other similar ring compounds.

• Bulletin of the Korean Chemical Society
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• v.24 no.2
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• pp.189-192
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• 2003

The reaction of 4-(2-methylaziridin-1-yl)-3-ureidobenzotrifluorides 4 with triphenylphosphine, carbon tetrachloride, and triethylamine (Appel's condition) led to the corresponding carbodiimides 5, which underwent intramolecular cycloaddition reaction with aziridine under the reaction condition to give the benzimidazolefused heterocycles, 2,3-dihydro-1H-imidazo[1,2-a]benzimidazoles 8 and 12,13-dihydro-5H-benzimidazo[2,3-b] [1,3]benzodiazepines 9.