Der elektronegativierende Effekt der Cyansubstitution am Kohlenstoffatom

Abstract

Cyanosubstitution of carbon atoms changes certain characteristic properties of many compounds in a similar way as do heteroatoms at the same place. A number of examples are  given from the literature for the effects of >C(CN)₂ and O respectively as structure elements in different compounds. Pairs of compounds containing ⪫C–CN and =N– at the same place in the molecule have been synthesized and are compared with respect to physical and chemical properties. The principle of similarity holds as long as the cyanosubstitution does not add to the possibilities for new mesomeric forms by taking over negative charges in dipolar canonic structures.