What is "ketyl"

n. (context organic chemistry English) Any of a class of organic radicals, R₂C-O^., formally derived from a ketone

A ketyl group in organic chemistry is an anion radical that contains a group =CO• in which an oxygen radical is bonded directly to carbon, negatively charged. This molecular entity is very unstable and appears in chemical reactions as a reactive intermediate.

Another mesomeric structure has the radical position on carbon and the negative charge on oxygen.

Ketyls can be formed as radical anions by one-electron reduction of carbonyls with alkali metals. Ketyls are also involved in the pinacol coupling reaction and the McMurry reaction.