Organocatalytic asymmetric 5-hydroxypyrrolidine synthesis: a highly enantioselective route to 3-substituted proline derivatives

The highly enantioselective organocatalytic tandem reaction between 2-acylaminomalonates and α,β-unsaturated aldehydes is presented. The reaction is a direct entry to 5-hydroxypyrrolidines and 3-substituted proline derivatives, which are furnished in high yields and 90–99% ee.