Directed Evolution of Nonheme Iron Enzymes for Enantioselective Aminative Difunctionalization of Alkenes
Fei Liu, S F. Li, Zi-Shan Fan, Jiahua Luo, Xue Zeng, Wei Long, Li Ye, Jiayao Li, Yongxiang Zheng, Xin Wang, Chun Zhang, Peng Chen, Zhi‐Jun Jia
Abstract
High Resolution Image Download MS PowerPoint Slide The direct aminative difunctionalization of alkenes offers a powerful strategy for synthesizing valuable amine-containing compounds. However, achieving this transformation enantioselectively remains a significant challenge in both synthetic chemistry and biocatalysis. In this study, we engineered a nonheme iron enzyme, quercetin 2,3-dioxygenase from Bacillus subtilis ( Bs QueD), to catalyze three distinct alkene aminofunctionalization reactions with high efficiency and enantiocontrol. Through directed evolution, we developed an optimized Bs QueD variant capable of producing a wide array of chiral 2-azidoamines, 2-aminothiazolines, and 2-aminooxazolines with up to 72% yield and 99:1 enantiomeric ratio (e.r.). Mechanistic investigations suggest a stepwise radical addition pathway. This work broadens the scope of biocatalytic alkene difunctionalization, providing a sustainable and efficient route for synthesizing diverse chiral primary amines.