Base-Catalysed Epimerization Behavior and Unusual Reactivity of N-Substituted Derivatives of 2,5-Dicarbalkoxypyrrolidine. Preparation of a Novel Mixed Carbamic Carbonic Anhydride by a 4-(Dimethylamino)pyridine-Catalyzed Acylation

Article abstract of DOI:10.1021/jo00259a023

The equilibration of cis-trans isomers of 1-substituted 2,5-dicarbalkoxypyrrolidine derivatives (1 = CH2Ph, H, CN, CO2R) results in nearly 1:1 mixtures, contrary to a literature report for 1-benzyl-2,5-dicarbalkoxypyrrolidine.Apparent conversion to the tr