2-formylbenzonitrile

The title compound, C8H5NO, has an intramolecular O center dot center dot center dot CN contact involving an O center dot center dot center dot C distance of 2.797 ( 2) angstrom and a C-C - N bond angle of 174.5 ( 2) degrees, both indicative of a weak nucleophilic attack of the aldehyde O atom on the electrophilic C atom in the nitrile group. Calculations at the B3LYP density functional level using the 6 - 31G* basis set support this interpretation; natural bond-order analysis indicates an n(O1) --> pi*(CN) delocalization energy of 6.3 kJ mol(-1). Similar results were obtained from density functional calculations on three related molecules. The 2-formylbenzonitrile molecules pack in sheets as a consequence of C - H center dot center dot center dot N and C - H center dot center dot center dot O hydrogen bonds.