• Bulletin of the Korean Chemical Society
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• v.26 no.4
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• pp.599-602
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• 2005

The aromatic fluorination method involving the acid-catalyzed decomposition of a triazene in an ionic liquid is a very convenient and efficient way to prepare a variety of aromatic fluorides in a lab-scale. It should be particularly useful for the preparation aryl fluorides substituted with electron withdrawing substituents. Fluorination of triazene 1 (1.0 mmol) and p-toluenesulfonic acid (1.2 mmol) in an ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][$BF_4$], 2.5 mL) proceeds very smoothly at 80 ${^{\circ}C}$ with or without an external source of fluoride, providing 73% yield in 30 min. Unlike diazonium salts, triazene precursors are stable enough to be stored for a long period of time without a noticeable decomposition.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.1-5
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• 2018

In this study, we designed and synthesized novel thermal radical initiators of BTAP (1-phenyl-3,3-dipropyltriazene), BTACP (1-(phenyldiazenyl)pyrrolidine), BTACH (1-(phenyldiazenyl)piperidine), and BTACH7 (1-(phenyldiazenyl)azepane) based on a triazene moiety to provide a thermal initiator for radical polymerization. The synthetic method is valuable due to the simplicity. In addition, the synthesized thermal initiator did not affect the color of the polymer. Among the four initiators, the polymerization time for the BTACH of the 6-membered ring decreased by 67%, as opposed to the polymerization time without initiator. Conversion after polymerization was over 92%. DSC experiments also showed that the initiator with hexagonal rings had the lowest peak polymerization temperature of $160^{\circ}C$. Our study suggests a promising new initiator system that is effective for radical polymerization.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.239-245
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• 1996

Fungicidal activity has been examined for a series of substituted phenylhydrazono-3-methyl-1,2-isoxazol-5-one against plant pathogenic fungi. 3-methyl isoxazol-5-one was obtained from ethyl acetoacetate and hydroxyl amine. Final products were prepared by aromatic diazo coupling with 3-methyl isoxazol-5-one. Fungicidal activities against Rhizoctonia solani, Colletotrichum gloeosporioides, Cladosporium cucumerinum, Pythium ultimum were tested and Pythium ultimum were tested and Pythium ultimum was selected for quantitative measurement of activity. Methyl, halogen, nitro derivatives possessed high fungicidal activity at p-, o-, p- position, respectively. Methyl, halogen derivatives were much more active than alkoxy, nitro derivatives and the order of activity of halogen derivatives was F > Cl > I. This result implied that the activity was related to the molecular volume of substitutents.

• Journal of Ecology and Environment
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• v.46 no.1
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• pp.62-75
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• 2022

Background: Pollinators help plants to reproduce and support economically valuable food for humans and entire ecosystems. However, declines of pollinators along with population growth and increasing agricultural activities hamper this mutual interaction. Nectar and pollen are the major reward for pollinators and flower morphology and volatiles mediate the specialized plant-pollinator interactions. Limited information is available on the volatile profiles attractive to honey bees and bumblebees. In this study we analyzed the volatile organic compounds of the flowers of 9 different plant species that are predominantly visited by honey bees and bumblebees. The chemical compositions of the volatiles were determined using a head space gas chromatography-mass spectrometry (GC-MS) method, designed to understand the plant-pollinator chemical interaction. Results: Results showed the monoterpene 1,3,6-octatriene, 3,7-dimethyl-, (E) (E-𝞫-ocimene) was the dominating compound in most flowers analyzed, e.g., in proportion of 60.3% in Lonicera japonica, 48.8% in Diospyros lotus, 38.4% Amorpha fruticosa and 23.7% in Robinia pseudoacacia. Ailanthus altissima exhibited other monoterpenes such as 3,7-dimethyl-1,6-octadien-3-ol (𝞫-linalool) (39.1%) and (5E)-3,5-dimethylocta-1,5,7-trien-3-ol (hotrienol) (32.1%) as predominant compounds. Nitrogen containing volatile organic compounds (VOCs) were occurring principally in Corydalis speciosa; 1H-pyrrole, 2,3-dimethyl- (50.0%) and pyrimidine, 2-methyl- (40.2%), and in Diospyros kaki; 1-triazene, 3,3-dimethyl-1-phenyl (40.5%). Ligustrum obtusifolium flower scent contains isopropoxycarbamic acid, ethyl ester (21.1%) and n-octane (13.4%) as major compounds. In Castanea crenata the preeminent compound is 1-phenylethanone (acetophenone) (46.7%). Conclusions: Olfactory cues are important for pollinators to locate their floral resources. Based on our results we conclude monoterpenes might be used as major chemical mediators attractive to both honey bees and bumblebees to their host flowers. However, the mode of action of these chemicals and possible synergistic effects for olfaction need further investigation.