Fig. 1: Reaction pathways to synthesize succinonitrile.
From: Photocatalytic dehydrogenative C-C coupling of acetonitrile to succinonitrile

a Nucleophilic addition pathway applied in industrial synthesis; (b) Carbanionic coupling pathway; (c) oxidative radical coupling pathway and d the photocatalytic dehydrogenative coupling of acetonitrile proposed in this work.