Reductive C-C Coupling from α,β-Unsaturated Nitriles by Intercepting Keteniminates

We present an atom-economic strategy to catalytically generate and intercept nitrile anion equivalents using hydrogen transfer catalysis. Addition of alpha,beta-unsaturated nitriles to a pincer-based Ru-H complex affords structurally characterized kappa-N-coordinated keteniminates by selective 1,4-hydride transfer. When generated insitu under catalytic hydrogenation conditions, electrophilic addition to the keteniminate was achieved using anhydrides to provide alpha-cyanoacetates in high yields. This work represents a new application of hydrogen transfer catalysis using alpha,beta-unsaturated nitriles for reductive C-C coupling reactions.