Reactions of arylaldimines of glycine ethyl ester with halo-substituted arylideneacetones

Abstract

The reaction of 1,3-dipolar cycloaddition of para -halosubstituted mono- and diarylideneacetones and azomethine ylides generated in situ from N -arylimines of glycine ethyl ester in the presence of silver acetate and a half time excess of triethylamine afforded tetrasubstituted ethyl pyrrolidine carboxylates. For para -halogensubstituted dibenzyledeneacetone, a minor product with a different regioselectivity was observed. The selectivity of the reaction and the structure of the products were determined using NMR correlation spectroscopy. The regioselectivity of the cycloaddition was interpreted using DFT/PBE calculations of the transition state energies of the reactions.