Triphenylphosphine as an effective catalyst for ketoximes addition to acylacetylenes: regio- and stereospecific synthesis of (E)-(O)-2-(acyl)vinylketoximes

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• 作者：Boris A. Trofimov ; Tatyana E. Glotova ; Marina Yu. Dvorko ; Igor’ ; A. Ushakov ; Elena Yu. Schmidt ; Al’ ; bina I. Mikhaleva
• 关键词：Oximes ; Acylacetylenes ; Triphenylphosphine ; O-vinylation ; Isomerization
• 刊名：Tetrahedron
• 出版年：2010
• 出版时间：18 September 2010
• 年：2010
• 卷：66
• 期：38
• 页码：7527-7532
• 全文大小：690 K

文摘

Triphenylphosphine catalyzes the regio- and stereospecific addition of ketoximes to acylacetylenes, whereas classical conditions using acetylene (KOH/DMSO, 70 °C) are unsuitable for this purpose. The reaction proceeds under mild conditions (CH₂Cl₂, rt, 7 h) to afford (E)-(O)-2-(acyl)vinylketoximes (92–98 % stereoselectivity) in a yield of up to 85 % . The (E)-adducts obtained are energetically less favorable than the corresponding (Z)-isomers and are gradually enriched with (Z)-isomers, thus indicating the kinetic control of (E)-stereoselectivity of the reaction.