• Title/Summary/Keyword: boron trifluoride

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Boron Trifluoride Etherate on Alumina-A Modified Lewis Acid Reagent(Ⅱ). Alkylation of 5-(1,1-dimethylheptyl)-Resorcinols

  • Baek Seung-Hwa;Kim Hak-Jin
    • Bulletin of the Korean Chemical Society
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    • v.13 no.2
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    • pp.117-118
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    • 1992
  • Boron trifluoride etherate on alumina catalyses the condensation 5-(1,1-dimethylheptyl)-resorcinol, monoalkyl-5-(1,1-dimethylheptyl)-resorcinol and 5-(1,1-dimethylheptyl)-resorcinol dimethyl ether with 1-methyl-2-cyclohexen-l-ol. The products obtained was good to excellent yields.

Boron Trifluoride Etherate on Alumina-Modified Lewis Acid Reagent(III): Synthesis of 5-alkyl-3-(1-thioxolanyl-cyclohexenyl)-resorcinol Derivatives

  • Baek, Seung-Hwa;Lee, Chang-Joon
    • Archives of Pharmacal Research
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    • v.15 no.1
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    • pp.5-8
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    • 1992
  • 5-Alkyl-3-(1-thioxolanyl-cyclohexenyl)-resorcinol derivatives are readily prepared by boron trifluoride-on-alumina-catalyzed formation of 5-alkylresorcinols with 1-thioxolanyl-2-cyclohexenol; their formation depends on the nature of the alkylgroup. The yield is the highest with 5-(1, 1-dimethylheptyl)-resorcinol. The one with 5-pentylresorcinol is higher than 5-methylresorcinol and resorcinol apparently because of steric effects. The yields of the products increases: 3a (10%), 3b (20%) 3c (48%) and 3d (77%).

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2-(Multimethoxy)phenyl-4-methylene-1,3-dioxolane: Ⅱ. Preparation and Cationic Polymerization of 2-(x,y,z- Trimethoxyphenyl)-4-methylene-1,3-dioxolane Derivatives

  • 장원철;공명선
    • Bulletin of the Korean Chemical Society
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    • v.20 no.10
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    • pp.1195-1199
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    • 1999
  • 2-(2,4,5-Trimethoxyphenyl)-4-methylene-1,3-dioxolane (1b), 2-(2,4,6-trimethoxyphenyl)-4-methylene-1,3-di-oxolane (2b), and 2-(3,4,5-trimethoxyphenyl)-4-methylene-1,3-dioxolane (3b) were prepared and polymerized with boron trifluoride. Boron trifluoride catalyzed reaction proceeded via mainly ring-opening polymerization and cyclization reaction to yield poly(keto ether) and 3(2H)-dihydrofuranone. The yields of polymer and cyclized product exhibited a dependency on the position of the methoxy substituents in the benzene ring of 2-phenyl-4-methylene-1,3-dioxolane derivatives. Electrophilic attack of methylene or oxygen atom on 4-meth-ylene-1,3-dioxolane ring were suggested for the polymerization and cyclization.

Boron Trifluoride Etherate-Catalyzed Formation of 3,4,5,6-Tetrahydro-7-hydroxy-2-(1,3-dithian-2-yl)-9-alkyl-2,6-methano-2H-1-benzoxocin Derivatives

  • Baek, Seung-Hwa;Yook, Chan-Nam;Park, No-Yeun
    • Bulletin of the Korean Chemical Society
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    • v.12 no.6
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    • pp.633-635
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    • 1991
  • 3,4,5,6-Tetrahydro-7-hydroxy-2-(1,3-dithian-2-yl)- 9-alkyl-2,6-methano-2H-1-benzoxocin derivatives are readily prepared by boron trifluoride etherate-catalyzed formation of 5-alkylresorcinols with 1-thioxolanyl-2-cyclohexenol. The yieldis the highest with 5-(1,1-dimethylheptyl)resorcinol. The one with 5-pentylresorcinol is higher than with 5-methylresordnol and resorcinol apparently because of steric effects. The yields of the product increase; 3a(7%), 3b(22%), 3c(38%) and 3d(50%).

Reduction of Selected Carbonyl Compounds with 8-Oxyquinoline Dihydroboronite. Selective Reduction of Aldehydes in the Presence of Ketones

  • Kim, Sung-Gak;Yang, Sung-Bong;Kang, Ho-Jung
    • Bulletin of the Korean Chemical Society
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    • v.5 no.6
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    • pp.240-244
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    • 1984
  • 8-Oxyquinoline dihydroboronite is prepared by mixing equimolar amounts of 8-hydroxyquinoline and borane-dimethyl sulfide complex in tetrahydrofuran at room temperature and its structure is determined by spectroscopic methods. The reagent is shown to be an extremely mild reducing agent and reduces aldehydes, cyclohexanones, and acid chlorides to some extent. The reagent in the presence of 0.1 equiv of boron trifluoride etherate in tetrahydrofuran at room temperature reduces selectively aldehydes in the presence of ketones, while the reagent in the presence of 1 equiv of boron trifluoride etherate rapidly reduces simple aldehydes and ketones but does not reduce carboxylic acids, esters, and amides.