Cyanation of Aromatic Compounds in a Gaseous Plasma

Article abstract of DOI:10.1021/ja00404a038

Aromatic compounds are directly cyanated by passing cyanogen and the respective compounds through a radio-frequency generated and inductively coupled glow discharge zone.Benzene and a wide variety of substituted benzenes (C6H5X: X = CH3, t-Bu, CF3, OH, F, Cl, Br, CHO) are cyanated providing a good yield of ortho-, meta-, para-, and ipso-substituted products.The relative amount of ipso product increases as the carbon-X bond dissociation energy decreases.The ratio of ortho to meta to para cyanated products demonstrates a slight preference for substitution on electron-rich positions.A plot of the meta/para yield ratio against ?_m - ?_p gives a ρ value of -0.5.It is proposed that electron impact on cyanogen produces CN^., which in turn attacks the aromatic, causing substitution.