• Title/Summary/Keyword: Regioselective reaction

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Highly Chemo- and Regioselective Reaction of Hydroxybenzenes in Acidic Ionic Liquid

  • Guo, Hui;Zhuang, Yu Wei;Cao, Jian;Zhang, Guo Bao
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2594-2596
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    • 2013
  • Highly chemo- and regioselective reaction of hydroxybenzenes with ${\alpha},{\beta}$-unsaturated compounds in acidic ionic liquid l-butyl-3-methylimidazolium hydrogen sulphate ([BMIM]HSO4) was reported for the first time. A series of oxa-Michael adducts and Friedel-Crafts alkylated products were synthesized with good yields. The acidic ionic liquid could be easily recycled for at least 5 times with only minor loss in activity.

A facile synthesis of 4-cyano-3,5-difluorophenol (4-cyano-3,5-difluorophenol의 새로운 합성법)

  • Song, Jeong-Sup
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.6
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    • pp.1308-1312
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    • 2006
  • 4-Cyano-3,5-difluorophenol, useful as intermediate in the manufacturing of liquid crystals, was prepared by the regioselective iodination of 3,5-difluorophenol to give 4-iodo-3,5-difluorophenol, which was then converted to 4-cyano-3,5-difluorophenol under a mild reaction condition. The reaction products were characterized by spectroscopic methods and confirmed by comparison of these analytical data with reported values in the literatures.

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Retention of Configuration; Mechanism Studies on the Reaction of Chlorosulfonyl Isocyanate with Ethers

  • Kim, Ji-Duck;Jung, Young-Hoon
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.242.2-243
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    • 2003
  • We have developed the novel one-pot synthetic method for regioselective N-protected amines, carbamates as a protective group of amines, through the reaction of various ethers with chlorosulfonyl isocyanate (CSJ). This synthetic method provides a simple and convenient alternative for the formation of carbamates, such as -NHMoc, -NHPoc. -NHCbz, -NHPnz, -NHTroc and -NHAloc, by varying the alkyl moiety of ethers. (omitted)

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Studies on the Regioselective of Chlorosulfonyl Isocyanate with Cyclic ethers

  • Lim, Seung-Yong;Jung, Young-Hoon
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.183.1-183.1
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    • 2003
  • The synthesis of various cyclic carbamate compounds and amino alcohols has attracted attention in the past because of their potential as antibiotics, antitumor, analgenics, anticonvulsants. Several methods for the preparation of cyclic carbamate compounds have previously been reported including the use of heterocumulenes. We have recently described the novel synthetic method for N-protected amines from various ethers using Chlorosulfonyl isocyanate(CSI) and found that the mechanism of our CSI reaction is a competitive reaction of $S_N1$ and $S_ Ni$ mechanisms according to the stability of carbocation intermediates. (omitted)

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