Access to Vinyl Ethers and Ketones with Hypervalent Iodine Reagents as Oxy‐Allyl Cation Synthetic Equivalents
作者:Nina Declas、Jerome Waser
DOI:10.1002/ange.202006707
日期:2020.10.5
use of hypervalent iodine reagents. Under mild basic conditions, the addition of nucleophiles to aryloxy‐substituted vinylbenziodoxolone (VBX) reagents, easily available in two steps from silyl alkynes, resulted in the stereoselective formation of substituted aryl enol ethers. The reaction was most efficient with phenols as nucleophiles, but preliminary results were also achieved for C‐ and N‐ nucleophiles
摘要我们报告了烯醇醚的 Umpolung 策略,基于使用高价碘试剂生成氧烯丙基阳离子当量。在温和的碱性条件下,将亲核试剂添加到芳氧基取代的乙烯基苯并氧酮(VBX)试剂中,可以通过两步从甲硅烷基炔中轻松获得,从而立体选择性地形成取代的芳基烯醇醚。当酚类作为亲核试剂时,该反应最有效,但对于 C- 和 N- 亲核试剂也取得了初步结果。在没有外部亲核试剂的情况下,试剂的 2-碘苯甲酸酯基团被转移。获得的芳基烯醇醚可以通过氧化转化为α-双官能化酮。所描述的“烯丙基阳离子”样反应性与烯基碘鎓盐的成熟“乙烯基阳离子”行为形成对比。