Development of Aliphatic Alcohols as Nucleophiles for Palladium-Catalyzed DYKAT Reactions: Total Synthesis of (+)-Hippospongic Acid A
作者:Barry M. Trost、Michelle R. Machacek、Hong C. Tsui
DOI:10.1021/ja050340q
日期:2005.5.1
The ability to use aliphatic alcohols as competent nucleophiles in the palladium-catalyzed dynamic kinetic asymmetric transformation of Baylis-Hillman adducts is explored. High yield and enantioselectivity is obtained for both the kinetic transformation and dynamic kinetic transformation. The absolute stereochemistry of the products is used to explore the reactive conformation of 2-substituted pi-allyl
探索了在钯催化的 Baylis-Hillman 加合物的动态动力学不对称转化中使用脂肪醇作为感受态亲核试剂的能力。动力学转化和动态动力学转化均获得高产率和对映选择性。产品的绝对立体化学用于探索 2-取代的 pi-烯丙基配合物与基于 DPPBA 的手性配体的反应构象。在原肠形成抑制剂 (+)-河马酸 A 的简明全合成的背景下进一步证明了该方法的实用性。该合成具有三个钯催化的烯丙基烷基化反应,以引入三种不同的键类型:CS、CH 和公司。