Cu- and Pd-Catalyzed Asymmetric One-Pot Tandem Addition−Cyclization Reaction of 2-(2‘,3‘-Alkadienyl)-β-keto Esters, Organic Halides, and Dibenzyl Azodicarboxylate:  An Effective Protocol for the Enantioselective Synthesis of Pyrazolidine Derivatives

Optically active pyrazolidine derivatives have been constructed by the Cu- and Pd-catalyzed asymmetric one-pot tandem addition−cyclization reaction of 2-(2‘,3‘-dienyl)-β-ketoesters, organic halides, and dibenzyl azodicarboxylate. The absolute configurations of the final products depend on the structure of the ligand.