• Title/Summary/Keyword: bromo

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Carbonylation of Bromo(Bromomethyl)Benzenes to Alkyl Carboalkoxyphenylacetates Catalyzed by Cobalt Carbonyl

  • Shim, Sang-Chul;Doh, Chil-Hoon;Lee, Dong-Yub;Youn, Young-Zoo;Lee, Seung-Yub;Chae, Shin-Ae;Oh, Dae-Hee;Oh, Hun-Seung
    • Bulletin of the Korean Chemical Society
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    • v.13 no.1
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    • pp.45-48
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    • 1992
  • A synthetic method for bis-carbonylation of bromo(bromomethyl)benzenes was described. Alkyl carboalkoxyphenylacetates were easily prepared by the carbonylation of benzylic and arylic bromide moieties in bromo(bromomethyl)benzenes with alcohols in the presence of $K_2CO_3,\;CH_3I$, and a catalytic amount of cobalt carbonyl under the atmospheric pressure of carbon monoxide at room temperature in good to excellent yields. The base played a decisive role in the selectivity of product and $K_2CO_3$ was the best one among bases used.

A Facile Preparation of 2-(2-Hydroxyethyl)homoallenylsilanes Using In Situ Generated Homoallenylindium Reagent

  • Lee, Pil Ho;Bang, Geuk Chan;An, Hyo Sun;Lee, Gu Yeon
    • Bulletin of the Korean Chemical Society
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    • v.22 no.12
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    • pp.1385-1389
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    • 2001
  • In situ generated homoallenylindium reagents derived from the reaction of indium with 4-bromo-3-[(tri-methylsilyl) methyl]-1,2-butadiene reacted with a variety of aldehydes in DMF to produce 2-(2-hydroxy-ethyl) homoallenylsilanes at room temperatu re in good to excellent yields. 2- or 3-Hydroxybenzaldehyde that contains labile hydrogen was reacted with homoallenylindium reagent to provide the homoallenylsilanes. In the case of 4-formylbenzoic acid, the desired compound was produced in 88% yield. 4-Bromo-3-[(trimethyl-silyl) methyl]-1,2-butadiene was prepared from monoacetylation and mesylation of 2-butyn-1,4-diol, addition of trimethylsilylmethyl anion, saponification and mesylation followed by Finkelstein reaction.

5-Bromo-Ph4-BTPhen Ligand for Selective Removal of Strontium and Cobalt From Water

  • Jang, Jiseon;Harwood, Laurence M.;Cowell, Joe;Afsar, Ashfaq;Lee, Dae Sung
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2018.05a
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    • pp.183-183
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    • 2018
  • In this study, 5-bromo-2,9-bis(5,6-diphenyl-1,2,4-triazin-3-yl)-1,10-phenanthroline (5-bromo-Ph4-BTPhen) was synthesized and evaluated for its ability to remove major radionuclides ($Cs^+$, $Sr^{2+}$, and $Co^{2+}$). The synthesized ligand removed both $Sr^{2+}$ and $Co^{2+}$ from $1mg\;L^{-1}$ aqueous solutions with extraction efficiencies of up to 99% at neutral and alkaline pH. The $Sr^{2+}$ and $Co^{2+}$ removal efficiencies decreased as a consequence of the higher bonding strengths of competing metal ions to the N-donor atoms in the cavity of the ligand; competing divalent ions affected the $Sr^{2+}$ and $Co^{2+}$ removal efficiencies more than monovalent ions.

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A Novel Photonuclease; Bromofluoroacetophenone Analogs

  • Jeon, Raok
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2001.11a
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    • pp.81-81
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    • 2001
  • The photoinducible DNA cleaving activities of bromofluoroacetophenones as a novel photonuclease were investigated. The photolytic behavior and DNA cleaving acitivity of fluorine derivative were compared with those of non-fluorine substituted compound, 4'-bromoacetophenones. Although the DNA cleaving activities of fluorine analogs were similar with those of 4'-bromoacetophenones, ο-bromo-$\rho$-fluoro derivatives gave the better DNA cleaving activities than $\rho$-bromo-ο-fluoro derivatives did.

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Antimicrobial and Antineoplastic Tyrosine Metabolites from a Marine Sponge, Aplysina fistularis

  • Goo, Yang-M.
    • Archives of Pharmacal Research
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    • v.8 no.1
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    • pp.21-30
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    • 1985
  • Examination of the constituents of a marine sponge, Aplysina fishtularis, indicated that brominated tyrosine metabolites were mainly responsible for antimicrobial and antineoplastic activities. Halogenated tyrosine metabolites, 2, 6-dibromo-(2), 2-bromo-3-chloro-(3) and 2, 6-dibromo-(5), 5-a mino-2-bromo-6-chloro-(6) and 5-amino-2, 6-dich-loro-(7) 4-hydroxy-2-cyclohexenone-4-acetic acid lactams were identified as the major antineoplastic and antimicrobial principles. Many other brominated tyrosine metabolites were also confirmed, but they did not show antimicrobial and antineoplastic activities.

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New Radical Allylation Reactions Using 2-Bromo-3-(phenylthio)propene and Their Application to the Synthesis of Carbocyclic Compounds

  • 유병우;Dennis P. Curran
    • Bulletin of the Korean Chemical Society
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    • v.17 no.11
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    • pp.1009-1018
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    • 1996
  • A study on the application of vinyl radical cyclization via free radical allylation reaction in the synthesis of various carbocyclic compounds is described. In connection with this study, a new allyl transfer reagent, 2-bromo-3-(phenylthio)propene 1 is developed and it was shown that vinyl radical cyclization through free radical allylation reaction using reagent 1 provides a valuable approach to carbocyclic systems with a reactive exo-alkylidene moiety, which is advantageous for further transformations.

3-halohydantoins as halolactonization reagents

  • Cook, Chae-Ho;Jew, Sang-Sup;Chung, You-Sup
    • Archives of Pharmacal Research
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    • v.5 no.2
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    • pp.103-106
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    • 1982
  • By the reaction of 15 with 3-halohydantoins (4-14) in N, N-dimethylformamide, which were prepared from corresponding hydantoins, 3-bromo-5, 5-dimethylhydantoin was found to be the most convenient reagent for halolactonization reaction.

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