Asymmetric intramolecular [3 + 2] cycloaddition reactions of acylhydrazones/olefins using a chiral zirconium catalyst

J Am Chem Soc. 2002 Nov 20;124(46):13678-9. doi: 10.1021/ja027681d.

Abstract

Catalytic asymmetric intramolecular [3 + 2] cycloaddition of hydrazone/olefins has been attained. In the presence of a chiral zirconium catalyst prepared from zirconium alkoxide and a BINOL derivative, the desired pyrazolidine derivatives were obtained in high yields with high selectivities. The products were easily converted to 1,3-diamine or beta-aminonitrile derivatives by N-N bond cleavage.