Enantiocontrolled Synthesis of 3‐Pyrrolines from α‐Amino Allenes

Cyclization of α‐amino allenes in the presence of N‐bromosuccinimide afforded pyrrolines in good yields. The products were obtained with high enantiomeric excesses when optically active allenes were used as substrates. The synthesis of a 2,5‐dehydroprolinol derivative is also presented. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)