The activation of C-C bonds by transition-metal complexes is of continuing interest and acetonitrile (MeCN) has attracted attention as a cyanide source with comparatively low toxicity for organic cyanation reactions. A diiron end-on μ-η 1 :η 1 -CN-bridged complex was obtained from a crystallization experiment of an open-chain iron-NHC complex, namely, μ-cyanido-κ 2 C:N-bis{[(acetonitrile-κN)[3,3'-bis(pyridin-2-yl)-1,1'-(methylidene)bis(benzimidazol-2-ylidene)]iron(II)} tris(hexafluorophosphate), [Fe 2 (CN)(C 2 H 3 N) 2 (C 25 H 18 N 6 ) 2 ](PF 6 ) 3 . The cyanide appears to originate from the MeCN solvent by C-C bond cleavage or through carbon-hydrogen oxidation.