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

Abstract

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.

Catalytic Olefin Transpositions Facilitated by Ruthenium N,N,N-Pincer Complexes

“…We previously developed a family of N,N,N-pincer ruthenium catalysts capable of performing reversible hydrogen transfer from alcohols, amines, and their dehydrogenated counterparts. [19][20][21][22][23] These catalytic hydrogen transfer reactions can be coupled to effect upgrading reactions of low-cost alcohols, and in a recent report of ethanol upgrading, 26 we discovered that the catalysts are also competent for cis-to-trans olefin isomerization. The aldehyde generated from alcohol dehydrogenation was intercepted with nucleophiles, including a tandem Wittig reaction.…”