Synthesis of substituted pyrrolin-4-ones from amino acids in mild conditions via a gold-catalyzed approach.

The gold-catalyzed cyclization of various alpha-amino-ynone derivatives gave the corresponding pyrrolin-4-ones in high yields. Moreover, the use of gold(III) oxide as catalyst allows a moderate to total stereocontrol during the cyclization. These pyrrolin-4-ones are highly useful intermediates for the synthesis of functionalized pyrrolidines and other natural products.