Highly Efficient and Diastereoselective Construction of Tricyclic Pyrrolidine‐Fused Benzo[ bb ]thiophene 1,1‐dioxide Derivatives viavia 1,3‐Dipolar [3?+?2] Cycloaddition

摘要

> A rapid and highly efficient 1,3‐dipolar [3?+?2] cycloaddition of nonstabilized azomethine ylides generated in situ with benzo[ b ]thiophene 1,1‐dioxides as the dipolarophiles has been developed. The efficient method affords tricyclic pyrrolidine‐fused benzo[ b ]thiophene 1,1‐dioxide derivatives in high to excellent yields (up to 99%) with excellent diastereoselectivities (up to 25:1 dr) under mild reaction conditions. The structure of a typical product was confirmed by X‐ray crystallography.