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

Article abstract of DOI:10.1002/anie.201904530

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