One-Pot Synthesis of 3-Substituted Isoxazoles from Phenyl Vinylic Selenide
Shou-Ri Sheng*, Xiao-Ling Liu, Qu Xu, Cai-Sheng Song
*Department of Chemistry, Jiangxi Normal University, Nanchang, 330027, P. R.
China, Email: shengsr
163.com
S.-R. Sheng, X.-L. Liu, Q. Xu, C.-S. Song, Synthesis, 2003, 2763-2764.
DOI: 10.1055/s-2003-44354
Abstract
A 1,3-dipolar cycloaddition of phenyl vinylic selenide to nitrile oxides and subsequent oxidation-elimination furnished 3-substituted isoxazoles with good yields in a one-pot, two-step transformation.
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Details
The document details a one-pot, two-step synthesis method for 3-substituted isoxazoles using phenyl vinylic selenide. The process involves 1,3-dipolar cycloaddition of nitrile oxides with phenyl vinylic selenide, followed by oxidation-elimination using 30% hydrogen peroxide. This method offers mild reaction conditions, convenient manipulation, and good yields. The study highlights that phenyl vinylic selenides, previously underutilized as dipolarophiles, can effectively produce isoxazoles, which are valuable in natural product synthesis and as molecular building blocks. The reaction yields varied depending on the substituents, with hydrogen as substituent yielding single products, while other substituents resulted in regioisomer mixtures. The procedure involves generating nitrile oxides in situ from aldoximes and N-chlorosuccinimide, followed by the addition of phenyl vinylic selenide and triethylamine. After stirring and cooling, hydrogen peroxide is added to facilitate oxidation. The resulting products are purified via silica gel column chromatography. The method's efficiency and simplicity make it a valuable addition to synthetic organic chemistry, particularly for producing heterocyclic compounds. The research was supported by the Natural Science Foundation of Jiangxi Province, China.
Key Words
isoxazoles, phenyl vinylic selenide, 1,3-dipolar cycloaddition, oxidation-elimination
ID: J66-Y2003-2120
