Tandem Enzyme/Gold-Catalysis: From Racemic α-Allenic Acetates to Enantiomerically Enriched 2,5-Dihydrofurans in One Pot

We report the first example of a tandem kinetic resolution/cycloisomerization of racemic allenic acetates in the presence of Burkholderia cepacia lipase (PS Amano SD) and catalytic amounts of chloroauric acid (HAuCl4) which affords 2,5-dihydrofurans, as well as unreacted starting material, in one pot with high enantiomeric excess and moderate to good yield.