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The employment of α-trifluoromethyl α,β-unsaturated esters as dipolarophiles pose considerable challenge due to expeditious defluorination and intrinsic steric hindrance. The present work provides an efficient access to valuable pyrrolidines bearing a trifluoromethylated all-carbon quaternary stereocenter through copper/M7-catalyzed asymmetric dipolar cycloaddition of α-trifluoromethyl α,β-unsaturated esters with azomethine ylides. The products were obtained in up to 98% yield with up to >20:1 d.r. and 99% ee. A broad substrate scope, good functional group tolerance, high stereoselectivity, as well as diverse synthetically valuable transformations of the products make this approach highly attractive.

The polymer-bound Ming-Phos was easily prepared by the highly efficient immobilization of our recently developed Ming-Phos in polystyrene by copolymerization in the presence of 5% DVB, which shows good performance in the application of heterogeneously catalyzed asymmetric cycloaddition. A pair of enantiomers of the product with opposite configurations could be easily delivered in high yields with excellent enantioselectivity by the application of two diastereomers of the heterogeneous catalyst. This heterogeneous catalyst not only exhibits similar catalytic activity and enantioselectivity to those of the homogeneous catalyst but also could be easily recovered and recycled for up to eight cycles.