Nitrile anion
Nitrile anions is jargon from the organic product resulting from the deprotonation of alkylnitriles. The proton(s) α to the nitrile group are sufficiently acidic that they undergo deprotonation by strong bases, usually lithium-derived. The products are not anions but covalent organolithium complexes. Regardless, these organolithium compounds are reactive toward various electrophiles. Although nitrile anions are functionally similar to enolates, the extra multiple bond in nitrile anions provides them with a ketene-like geometry. Additionally, deprotonated cyanohydrins can act as masked acyl anions, giving products impossible to access with enolates alone. (Wikipedia).
