A convenient procedure for the catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides and alkenes.

[reaction: see text] Silver fluoride and cinchona alkaloids catalyze the diastereo- and enantioselective 1,3-dipolar cycloaddition between azomethine ylides, generated from N-alkylideneglycine esters, and acrylates to give the corresponding endo-adducts. Azomethine ylides derived from aromatic and aliphatic aldehydes react in a highly diastereoselective reaction with good yields and enantioselectivities of the substituted pyrrolidines.