Copper-Catalyzed Enantioselective (3 + 3) Cycloaddition of Ethynyl Methylene Cyclic Carbamates with N , N′ -Cyclic Azomethine Imines

作者：Yahui Li, Xiang‐Ping Hu · 发表于：Organic Letters · 年份：2025 · DOI：10.1021/acs.orglett.5c01114 · 被引用次数：5 · 研究领域：Synthesis and Catalytic Reactions、Asymmetric Synthesis and Catalysis、Catalytic C–H Functionalization Methods

A copper-catalyzed asymmetric cross 1,3-dipolar cycloaddition between 2-aminoallyl zwitterions generated in situ from ethynyl methylene cyclic carbamates and N, N′ -cyclic azomethine imines has been realized. The reaction, which utilizes a commercially available chiral tridentate N -ligand, delivers a range of functionally rich chiral hexahydro-8 H -pyrazolo[1,2- a ][1,2,4]triazin-8-one derivatives in 51–99% yields with good to high enantioselectivities (44–95% ee).