Stereocontrol in Asymmetric S<sub>E</sub>′ Reactions of γ-Substituted α,β-Unsaturated Aldehydes
作者:David R. Williams、Bruce A. Atwater、Seth A. Bawel、Pucheng Ke、Osvaldo Gutierrez、Dean J. Tantillo
DOI:10.1021/ol403351x
日期:2014.1.17
Asymmetric SE′ reactions of (E)- and (Z)-γ-substituted-α,β-unsaturated aldehydes have been studied for the stereocontrolled preparation of nonracemic alcohols. Mild exchange reactions of allylic stannanes provide access to chiral 1,3-bis(tolylsulfonyl)-4,5-diphenyl-1,3-diaza-2-borolidines. These reagents display reactivity with the γ-substituted α,β-unsaturated aldehydes, which is characterized by
已经研究了(E)-和(Z)-γ-取代的α,β-不饱和醛的不对称S E '反应,用于立体控制非外消旋醇的制备。烯丙基锡烷的温和交换反应可提供手性1,3-双(甲苯磺酰基)-4,5-二苯基-1,3-二氮杂-2-硼烷核苷。这些试剂与γ-取代的α,β-不饱和醛具有反应性,其特征在于立体控制的元素匹配和错配。计算分析(使用密度泛函理论)提供了宝贵的见识,可指导反应的发展。
Total Synthesis of (−)-2-<i>epi</i>-Peloruside A
作者:Amos B. Smith、Jason M. Cox、Noriyuki Furuichi、Craig S. Kenesky、Junying Zheng、Onur Atasoylu、William M. Wuest
DOI:10.1021/ol8019132
日期:2008.12.18
A convergent synthesis of (-)-2-epi-peloruside A has been achieved. Highlights include implementation of multicomponent type I anion relay chemistry (ARC) to unite 2-TBS-1,3-dithiane with two epoxides to construct the eastern hemisphere, a late-stage dithiane union to secure the complete, fully functionalized carbon backbone, and Yamaguchi macrolactonization, which led to (-)-2-epi-peloruside A via an unexpected epimerization at C(2).