Enantioselective Rhodium‐Catalyzed Allylic Alkylation of β,γ‐Unsaturated α‐Amino Nitriles: Synthetic Homoenolate Equivalents
作者:Timothy B. Wright、Ben W. H. Turnbull、P. Andrew Evans
DOI:10.1002/anie.201900442
日期:2019.7.15
An enantioselective rhodium‐catalyzed allylic alkylation of β,γ‐unsaturated α‐amino nitriles is described. This protocol provides a novel approach for the construction of β‐stereogenic carbonyl derivatives via the catalytic asymmetric alkylation of a homoenolate equivalent. The particularly challenging nature of this transformation is highlighted by the fact that three modes of selectivity must be
描述了β,γ-不饱和α-氨基腈的对映体选择性铑催化的烯丙基烷基化反应。该方案为通过均烯酸酯等同物的催化不对称烷基化提供了一种构建β-立体异构羰基衍生物的新方法。这一转变特别具有挑战性,因为除了几何控制外,还必须操纵三种选择性模式,即区域选择性和对映选择性。γ-立体异构的氰基烯胺产品可以很容易地就地水解以提供β-取代的羧酸,从而可以方便地获得许多相关的羰基衍生物。另外,对照实验表明,手性铑烯丙基中间体可促进E的选择性形成。氰基烯胺产品,这一点至关重要,因为Z异构体的对映体控制量大大降低。