Nickel-Catalyzed Cyanation of Benzylic and Allylic Pivalate Esters

A nickel-catalyzed cyanation reaction of benzylic and allylic pivalate esters is reported using an air-stable Ni(II) precatalyst and substoichiometric quantities of Zn(CN)(2). Alkene additives were found to inhibit catalysis, suggesting that avoiding beta-hydride elimination side reactions is essential for productive catalysis. An enantioenriched allylic ester undergoes enantiospecific cross-coupling to produce an enantioenriched allylic nitrile. This method was applied to an efficient synthesis of (+/-)-naproxen from commercially available starting materials.