Indirect Electroreductive Cyclization of N-Allyl and N-Propargylamides Using a Nickel(II) Complex as an Electron-Transfer Catalyst : Selective Formation of Halogenated and Non-halogenated Pyrrolidinones

Abstract

Nickel(II) complex-catalyzed indirect electroreduction of N-allyl and N-propargyl-α-bromoamides conducted in dimethylformamide with 2 eq of a hydrogen atom donor, diphenylphosphine, afforded the corresponding pyrrolidinones as the sole cyclized product in good yields, while that of N-allyl-α-iodoamides in acetonitrile gave the iodinated pyrrolidinones. Under both conditions the trans-C-3 : C-4 pyrrolidinones were formed predominantly.