Metal-catalysed radical cyclisations leading to N-heterocycles: new approaches to gabapentin and pulchellalactam

The copper(I) or ruthenium(II)-mediated radical cyclisation of halo-amides has been utilised to afford functionalised pyrrolidinones via 5-endo-trig or 5-exo-trig radical cyclisation pathways. This methodology has been applied to novel and concise syntheses of the anti-epileptic drug gabapentin and the biologically active natural product pulchellalactam.