Transforming Racemic Compounds into Two New Enantioenriched Chiral Products via Intermediate Kinetic Resolution
Jian Zhang, Mingyang Song, Weijun Tang, Dong Xue, Jianliang Xiao, Huaming Sun, Chao Wang
Abstract
Converting racemic compounds to enantioenriched products is an important and economic approach for accessing enantioenriched chiral molecules. A common method is kinetic resolution. Herein, we present a mode of kinetic resolution that transforms racemic compounds into enantioenriched products, in which the kinetic resolution of reaction intermediates is the key. Catalyzed by a single Ru complex, racemic allylic alcohols are shown to react with a glycine-derived Schiff base to afford two chiral compounds, a δ-carbonyl product and a δ-hydroxy variant, with good yields and stereoselectivities (up to >20:1 dr, 99% ee, 920 s factor). Mechanistic studies suggest that multiple hydrogen transfer events exist in the reaction: a dehydrogenative coupling process, which leads to a pair of racemic intermediates, and a transfer hydrogenation-enabled kinetic resolution process that resolves the intermediates, alongside H 2 release at the catalyst.