New Convenient, Enantiospecific Synthesis of (S,S)- and (R,R)-2,2′- Bipyrrolidine Derivatives.

Abstract An enantiomeric pair of ( S , S )- and ( R , R )-bipyrrolidine derivatives has been prepared from D- and L-tartaric acids or D-mannitol as optically active starting materials. Taking advantage of the C 2 -symmetric nature of these chiral sources, the synthetic sequence has been established by using efficient side chain elongation, stereospecific conversion of a vicinal diol into a diazido group via S N 2 inversion, and pyrrolidine ring formation via intramolecular substitution as the key steps.