The catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides to substituted olefins provides a powerful and atom economical approach for the preparation of highly-functionalized pyrrolidines,1 which can serve as valuable building blocks for natural products,bio-active molecules and organocatalysts.2 Among them,enantiopure 3,4-diaminopyrolidines were found to be important scaffolds in HIV protease inhibitors,DPP-4 inhibitors as well as salen-type chiral ligands.3 However,despite the impressive effort made in asymmetric 1,3-dipolar cycloaddition during the past few decades,the process with β-amino α,β-unsaturated alkenes as dipolarphiles has rarely been explored.Based on previous work,4 the cycloaddition of azomethine ylides to β-amino nitroalkene catalyzed by a novel N,O-ligand/Cu(Ⅰ)complex is developed,affording 4-nitro-3-aminopyrrolidines in high yields with excellent diastereoselectivities and enantioselectivities.