In conclusion, the cyanoketenate anion, [NCCCO] -has been synthesized and characterized. The compound can be isolated as the [K(18-crown-6)] + salt 1 on a multigram scale in over 90% yield from commercially available reagents. Reactions of 1 with the electrophiles HCl, Ph3SiCl or CO2 give related structures in which the cyanoketenate fragment dimerizes to give a four-membered ring (products 2, 3 and 4, respectively). On the other, the parent cyanoketene is stabilized by reaction of 1 with the nucleophilic NHC IMes (5) allowing the inception of the parent cyanoketene. Work is ongoing in our laboratories to explore the reactivity of the fundamental cyanoketenate anion as a building block to more complex molecular architectures.