Zhang Tao, Zhang Zi-Yu, Kang Guowei, Sheng Tao, Yan Jie-Lun, Yang Yuan-Bin, Ouyang Yuxin, Yu Jin-Quan
Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Science. 2024 May 17;384(6697):793-798. doi: 10.1126/science.ado1246. Epub 2024 May 16.
Stereoselective construction of γ- and δ-stereocenters in carbonyl compounds is a pivotal objective in asymmetric synthesis. Here, we report chiral bifunctional oxazoline-pyridone ligands that enable enantioselective palladium-catalyzed remote γ-C-H (hetero)arylations of free cycloalkane carboxylic acids, which are essential carbocyclic building blocks in organic synthesis. The reaction establishes γ-tertiary and α-quaternary stereocenters simultaneously in up to >99% enantiomeric excess, providing access to a wide range of cyclic chiral synthons and bioactive molecules. The sequential enantioselective editing of two methylene C-H bonds can be achieved by using chiral ligands with opposite configuration to construct carbocycles containing three chiral centers. Enantioselective remote δ-C-H (hetero)arylation is also realized to establish δ-stereocenters that are particularly challenging to access using classical methodologies.
在羰基化合物中立体选择性构建γ-和δ-立体中心是不对称合成中的一个关键目标。在此,我们报道了手性双功能恶唑啉-吡啶酮配体,其能够实现钯催化的游离环烷羧酸的对映选择性远程γ-C-H(杂)芳基化反应,这些环烷羧酸是有机合成中重要的碳环结构单元。该反应能同时以高达>99%的对映体过量构建γ-叔碳和α-季碳立体中心,为多种环状手性合成子和生物活性分子的合成提供了途径。通过使用构型相反的手性配体,可以实现两个亚甲基C-H键的顺序对映选择性编辑,从而构建含有三个手性中心的碳环。还实现了对映选择性远程δ-C-H(杂)芳基化反应,以构建使用经典方法难以获得的δ-立体中心。