Cyclic Alkenenitriles: Copper-Catalyzed Deconjugative α-Alkylation.

An amido cuprate formed from CuCN and LDA allows a general deconjugative α-alkylation of cyclic alkenenitriles. Deprotonating cyclic alkenenitriles with LDA-CuCN avoids polymerization that otherwise plagues these alkylations and generates a reactive metalated nitrile for alkylations with a range of carbon and heteroatom electrophiles. The strategy provides an effective synthesis of quaternary 5-, 6-, and 7-membered cycloalk-1-enecarbonitriles substituted on the nitrile-bearing carbon.