Asymmetric Synthesis of Novel Biaryl Analogues with a Fused Chiral Bicyclic Bridge Using α-Amino Acids as Chiral Sources

A series of biaryl anologues with a fused bicyclic bridge were synthesised in a diastereoselectivity of up to 14:86 via an intramolecular cyclisation of an in situ generated N-acyliminium ion. The absolute configuration of products 9b-d and 10b-d was clearly defined by a combination of X-ray crystal-structural analysis, NOE difference, and CD experiments.