Carbonyl dicyanide revisited: in situ crystallization and NMR signatures.

The single crystal structure of carbonyl dicyanide was determined via in situ crystallization. Hirshfeld analysis reveals a dominant interaction between the nitrogen atoms and the electron-deficient carbon framework. The 13C NMR spectrum shows resonances at 140.4 ppm (CO) and 110.5 ppm (CN), respectively, with 1JCC coupling between the carbonyl and cyanide C-atoms at 100 Hz. The 15N NMR spectrum shows a resonance at 269 ppm.