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Yu, Kook Hyun
- Journal of the Korean Chemical Society
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- v.39 no.5
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- pp.414-420
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- 1995
$\alpha$-Bromo-$\omega$-fluoroalkanes are synthesized in 19∼55% yields from the reactions of dibromoalkanes with AgF and TBABr in acetonitrile at $82^{\circ}C$ for 20 minutes. The reaction is monitored with gas-chromatography. 1^H$ NMR and $19^F$ NMR-Spectrometer are used for identification of $\alpha$-Bromo-$\omega$-fluoroalkanes, difluoroalkane, fluoroalken and bromoalkene.
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Duchowicz, P.;Castro, E.A.
- Journal of the Korean Chemical Society
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- v.44 no.6
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- pp.501-506
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- 2000
Some previous linear equations to predict hydrocarbon heats of formation are generalized. The basic molecular descriptors used for the QSPR analysis are atoms and chemcal bonds. This particular choice makes the method extremely simple and quite inexpensive. The predictions for a set of 19 alkenes yield deviations which are similar to experimental uncertainties. Some possible extensions of the method are pointed out.
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Cho, Dae-Won;Mariano, Patrick S.
- Journal of the Korean Chemical Society
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- v.54 no.3
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- pp.261-268
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- 2010
In this account, three synthetic methodologies that serve as the basis for new strategies for the preparation of selected natural products are briefly introduced. One process, involving ruthenium carbene catalyzed ring rearrangement metathesis developed by Grubbs and his coworkers, transforms alkene-tethered cycloalkenes to thermodynamically more favored alkene-tethered cycloalkenes. Another ruthenium carbene promoted reaction, referred to as dienyne metathesis, was uncovered in early studies by Grubbs and his collaborators. This process converts dienynes to fused bicyclic conjugated dienes. Finally, a novel photo-electrocyclization reaction of pyridinium salts, which leads to the formation of 4-aminocyclopenten-3,5-diol derivatives, is discussed. Examples are provided to show the utility of these methodologies in natural product synthesis. Emphasis is given to studies in which pyridinium salt photochemistry is coupled with ring rearrangement and dienyne metathesis in routes for the synthesis of polyhydroxyalted indolizidine alkaloids and the construction of the tricyclic core of the lepadiformine and cylindricine alkaloids.
https://doi.org/10.5012/jkcs.2010.54.3.261 인용 PDF KSCI KPUBS HTML

Kang, Chang Deok;Kim, Seung Jun
- Journal of the Korean Chemical Society
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- v.42 no.2
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- pp.161-171
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- 1998
The geometrical parameters, vibrational frequencies, and IR intensities for primary ozonide (POZ), secondary ozonide (SOZ) and carbonyl oxide as the intermediates of alkene-ozone reaction have been predicted using high level ab initio quantum mechanical method with various basis sets. In general, the polarization function decreases bond lengths and bond angles, while the electron correlation effect increases bond lengths slightly. The electronic structure of carbonyl oxide has been predicted to be zwitterionic structure and energy difference between zwitterionic and diradical structure is evaluated to be 22.4 kcal/mol at TZ2P CISD level of theory. The experimental vibrational frequencies and IR intensities of POZ and SOZ will be compared and discussed with our high level theoretical predictions.
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