• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2057-2060
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• 2010

• 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.

• Korean journal of applied entomology
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• v.23 no.4 s.61
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• pp.215-220
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• 1984

Mulberry dwarf, paulownia witches' broom, jujube witches' broom, and sumach witches' broom are known to be associated with mycoplamalike organisms(MLO) in Korea. Simple microscopic detection of MLO infection in these plants was attempted. Periwinkle plant was also tested. Application of $0.2\%\;and\;0.4\%$ solution of Dienes' stain gave diagnoatic value for MLO-induced diseases of periwinkle and mulberry. Among the various plant parts examined, young herbaceous stem just below the apical part gave the best result. Density of staining reaction was proportional to disease severity. Longitudial sections were superior to transverse sections in confirming MLO infection by staining. Light source without blue filter was useful for increasing the color contrast between sieve tube and xylem vessel and for eliminating misinterpretation. Paulownia, jujube, and sumach samples gave no clear difference in staining reaction between healthy and diseased sections even when various modifications of Dienes' staining procedure were tried.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.954-958
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• 1994

The bleaching effect of chlorophyll a by two lipoxygenase isoenzymes (LOX-1, LOX-2) isolated from potato tuber(variety DEinma ) was studied. In the presence of LOX-1 or LOX0-2 with linoleic acid chlorophyll a bleaching occurred during two isoenzymes-mediated oxidation of linoleic acid. Chlorophyll a bleaching porceeded with decreasing in the formation of conjugated dienes form linoleic acidyb LOX-1 and LOX-2 . In the presence of chlorophyll a, LOX-2 showed a markable decrease inproduction of conjugated dienes from linoleic acid and a higher chlorophyll a bleaching activity. compared with LOX-1. These results suggest chlorophyll-bleaching reaction required intermediates formed during the peroxidation of linoleic acid by lipoxygenase isoenzymes, thus preventing formation of conjugated dienes.

• Bulletin of the Korean Chemical Society
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• v.6 no.6
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• pp.366-369
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• 1985

The reactions of (E)-1-hexenylboronic acid (1) or (E)-${\beta}$-phenylethenylboronic acid (2) with various olefins in acetonitrile at room temperature in the presence of lithium palladium chloride and triethylamine gave the corresponding (E, E)-conjugated dienes stereospecifically in good yields. (E)-${\beta}$-Phenylethenylboronic acid (2) was more reactive than (E)-1-hexenylboronic acid (1) in these vinylations. And these vinylations were also carried out catalytically when 10 mol % of lithium palladium chloride and cupric chloride, as the reoxidant of palladium, or 10 mol % of palladium acetate and mercuric acetate were added instead of stoichiometric amount of lithium palladium chloride.

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1064-1069
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• 1994

Chlorobis(isoprene)rhodium(Ⅰ) (3), prepared by olefin-exchange reaction of chlorobis(cyclooctene)rhodium dimer (2) with isoprene, reacted with benzaldimine 4 to give iminoacylrhodium(Ⅲ) ${\eta}^3$-1,2-dimethylallyl complex 6. Ligand-promoted reductive elimination of 6 by pyridine and P(OMe)$_3$ produced ${\beta},{\gamma}$-unsaturated ketimine 8, which was readily hydrolyzed to give ${\beta},{\gamma}$-unsaturated ketone 9. Other methyl branched dienes such as 2,3-dimethylbutadiene, 3-methyl-1,3-pentadiene, 2-methyl-1,3-pentadiene, 2,4-dimethyl-1,3-pentadiene, 3-methyl-1,4-pentadiene and 2-methyl-1,4-pentadiene, were applied the synthesis of ${\beta},{\gamma}$-unsaturated ketones. In case of 2,4-dimethyl-1,3-pentadiene, only ${\gamma},{\delta}$ -unsaturated ketone 25, 1,2-addition product, was obtained, may be due to the mono-olefin coordination.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2255-2260
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• 2010

In this study, some novel thiosubstituted butenyne (3a-d, 7b, 15b), butadiene (4a-b, 4d, 5a, 5c, 6b, 8e, 9c, 10b, 16b, 18e) and [3]cumulene (11a-b with isomer 3a-b, 12a with isomer 13a, 14b, 17e) compounds were synthesized from the reaction of 2H-pentachloro-1,3-butadiene with thiols. The new compounds were characterized by elemental analysis, mass spectrometry, UV-vis, IR, 1H NMR, NMR ($^{13}C$ or APT) spectroscopy.

• Journal of Elementary Mathematics Education in Korea
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• v.17 no.1
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• pp.165-184
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• 2013

In order to utilize Sphinx Puzzle in shape education or deductive reasoning, a lesson employing Dienes' six-stage theory of learning mathematics was structured to be applied to students of 6th grade of elementary school. 4 students of 6th grade of elementary school, the researcher's current workplace, were selected as subjects. The academic achievement level of 4 subjects range across top to medium, who are generally enthusiastic and hardworking in learning activities. During the 3 lessons, the researcher played role as the guide and observer, recorded observation, collected activity sheet written by subjects, presentation materials, essays on the experience, interview data, and analyzed them to the detail. A task of finding every possible triangle out of pieces of Sphinx Puzzle was given, and until 6 steps of formalization was set, students' attitude to find a better way of mathematical deduction, especially that of operational thinking and deductive thinking, was carefully observed and analyzed.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.829-837
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• 2002

Recently it was reported that cycloaddition of 6,6-disubstituted cyclohexa-2,4-dienone, 1 with cyclopentadiene gave solely the adduct of type 1.while its reaction with 1,3-cyclohexadiene gave both Ⅱ and Ⅲ. Semiempirical MO calculations were done to elucidate the origin of the selectivity difference between the two dienes. Cycloaddition of 1 with cyclopentadiene is controlled thermodynamically to give only 1-diene adduct by ΔGvalues of 10.6-20.3 kcal/mol, while its reaction with 1,3-cyclohexadiene does not show 1-diene/1-dienophile selectivity due to similar stabilities of the two adducts. Thermodynamic parameters also show that 두애 adducts are more fabourably fromed in the cycloadditions of 1 with both cyclopentadiene and 1,3-cyclohexadiene, which coincides with experimental observations. Cope rearrangements of endo adducts are another avenue to convert between 1-diene and 1-dienophile.

• Journal of Photoscience
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• v.6 no.1
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• pp.7-12
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• 1999

Irradiation of 1 , 4-diphenylbut-1-en-3-yne 1 and some p-quinones in dichloromethane with 300nm UV light yield tow types of adducts, i.e., p-quinomethanes and cyclobutanes, in which the former were produced via the rearrangement of the intially formed spiro-oxetene intermediates. On the other hadn 1 added to o-quinones to give three types of adducts, i.e., 1, 3-dienes, 1, 4-dioxenes, or spiro-oxetanes, in which the former were found to be applied to synthesize phenanthrene derivatives. A methoxy derivative of enyne 39 was synthesized to investigate the type of thephotoaddition to o-quinones, in which 1, 4-dioxenes were obatained.