Asymmetric organocatalytic multicomponent reactions for efficient construction of bicyclic compounds bearing bisacetal and isoxazolidine moieties

An organocatalytic multicomponent reaction ofN-protected hydroxylamines, acrylaldehyde and acetal-containing enones was developed. Bisacetal-containing bicyclic isoxazolidine derivatives bearing four continuous stereocenters were formed with excellent stereoselectivities. A plausible reaction pathway was proposed based on(18)O-labeling control experiments.