A Simple Synthesis of Polysubstituted Pyrrolidines by an Organocatalytic Three-Component Approach Featuring a One-Pot Condensation and [3+2]-Cycloaddition Reaction in Aqueous Medium.

A simple one-pot procedure was developed for [3+2]-cycloaddition reactions of a,ß-unsaturated aldehydes, diethyl aminomalonate, and aromatic aldehydes in the presence of diphenyl[(2S)-pyrrolidin-2-yl]methanol as catalyst. This reaction converts simple, commercially available, starting materials into densely functionalized polysubstituted pyrrolidines under mild conditions and in a fully stereoselective fashion. Moreover, the use of brine as the reaction medium has remarkable beneficial effects in preventing the formation of self-condensation byproducts, cutting the reaction time, and reducing the production of wastes. [ABSTRACT FROM AUTHOR]