Abstract
It has been found that N- [α- (piperidinocarbonyl) benzylidene] trimethylsilylmethylamine reacts with unsymmetrical dipolarophiles to give 2, 2, 4- or 2, 2, 3-trisubstituted pyrrolidines in the presence of tetrabutylammonium fluoride or trifluoroacetic acid, respectively.