Highly efficient and diastereoselective construction of substituted pyrrolidines bearing a quaternary carbon center via 1,3‐dipolar cycloaddition.

A general approach to substituted pyrrolidines via [3 + 2] cycloaddition between nonstabilized azomethine ylides and cyanosulfones was developed. The efficient method provides a series of substituted pyrrolidines bearing a quaternary carbon center in high yields (up to 98%) excellent diastereoselectivities (up to >25:1 dr) under ambient reaction conditions. [ABSTRACT FROM AUTHOR]