Efficient Two-Step Conversion of α,β-Unsaturated Aldehydes to Optically Active γ-Oxy-α,β-unsaturated Nitriles and Its Application to the Total Synthesis of (+)-Patulolide C
作者:Jun Tian、Noriyuki Yamagiwa、Shigeki Matsunaga、Masakatsu Shibasaki
DOI:10.1021/ol034944f
日期:2003.8.1
[reaction: see text] An efficient two-step conversion of alpha,beta-unsaturated aldehydes into optically active gamma-oxy-alpha,beta-unsaturated nitriles is described. First, catalytic asymmetric cyanation-ethoxycarbonylation using (S)-YLi(3)tris(binaphthoxide) (YLB) afforded chiral allylic cyanohydrin carbonate. Second, a [3,3]-sigmatropic rearrangement proceeded without racemization under thermal
[反应:见正文]描述了一种有效的两步转化法,将α,β-不饱和醛转化为旋光性的γ-氧基-α,β-不饱和腈。首先,使用(S)-YLi(3)三(联萘酚)(YLB)进行催化不对称氰化-乙氧基羰基化反应,得到手性烯丙基氰醇碳酸酯。其次,在热条件下进行[3,3]-σ重排而不消旋,得到γ-氧基-α,β-不饱和腈。路易斯酸对于重排也是有效的,并且反应在温和的条件下顺利进行。为了证明转化的效用,进行了(+)-帕特洛立德C的催化催化对映选择性全合成。