Synthesis of Chiral Cyclopentanones via Asymmetric Ring Expansion

Significance

In the presence of a Pd(0)/Trost ligand system, allenylcyclobutanols are efficiently and enantioselectively converted into chiral cyclopentanones via Pd-π-allyl directed ring expansion. A wide variety of allenyl and cyclobutyl substituents are tolerated, affording cyclopentanone products in good to excellent yields and enantiomeric excesses.