Chiral cyclic zwitterionic bipyridinium-4-olates for the diastereoselective synthesis of (R,S)- and (S,R)-trozamicol

Diastereoselective synthesis of new zwitterionic bicyclic lactams, scaffolds for construction of 2-substituted-4-hydroxy piperidine and its pipecolic acid derivatives

“…We recently reported the preparation of new cyclic zwitterionic intermediates via an intramolecular non-classical Corey–Chaykovsky ring-closing reaction. Their utility was demonstrated by the synthesis of stereoisomers of σ 1 -receptor agonists trozamicol 5 or the synthesis of (+)- and (−)-Geissman–Waiss lactone ( Scheme 1 ). 6 …”