Synthetic studies in the α-kainic acid (2,3-trans,3,4-cis-2-carboxy-4-isopropenylpyrrolidin-3-ylacetic acid) series

Abstract

The synthesis of (±)-cis- and (±)-trans-4-isopropenylpyrrolidin-3-ylacetic acids and the attempted synthesis of (±)-2,3-trans-,3,4-cis-2-carboxy-4-isopropenylpyrrolidin-3-ylacetic acid, α-kainic acid, by intramolecular ene reactions are described. The ene cyclisation reaction has been shown to be kinetically controlled with the relative stabilities of the transition states controlling the product distribution. No isomerisation of starting diene or product pyrrolidine occurs under the conditions of the reaction.