Palladium(II)-Catalyzed Intramolecular 1,4-Oxyacyloxylation of Conjugated Dienes. A Stereocontrolled Route to Fused Six-Membered Lactones and Pyrans
作者:Renzo C. Verboom、B. Anders Persson、Jan-E. Bäckvall
DOI:10.1021/jo0357667
日期:2004.4.1
Stereocontrolled palladium(II)-catalyzed intramolecular 1,4-oxidations of dienyl acids and alcohols proceed under mild conditions to give fused δ-lactones and pyrans, respectively, in good yields. The stereo- and regioselectivity was affected by the presence of LiCl and solvent composition (HOAc/acetone). The products obtained were used for further functionalizations using copper(I)-mediated reactions
立体控制的钯(II)催化的二烯酸和醇的分子内1,4-氧化在温和的条件下进行,分别以高收率得到稠合的δ-内酯和吡喃。立体选择性和区域选择性受LiCl和溶剂组成(HOAc /丙酮)的存在的影响。使用铜(I)介导的反应将获得的产物用于进一步的官能化。预先形成的二丁基氰基丙酸酯与含有乙酸烯丙酯的吡喃的化学计量反应产生了具有高γ选择性和高收率的顺式和反式稠合环系统。