Corps aromatiques nitrés XIX. Action du cyanure de potassium sur les corps aromatiques nitrés

The Preparation of Nitriles.

“…Four distinct types of action take place, often simultaneously: (a) reduction of a nitro group to an azo, azoxy, nitroso, or hydroxylamino group, (b) replacement of a nitro group by an alkoxy group if the reaction is conducted in alcoholic solution, (c) replacement of a hydrogen by the cyano group, and (d) replacement of the nitro group by the cyano group. The last type requires very reactive nitro groups, de Bruyn reports an example of an alkoxydinitrobenzonitrile being converted to a phthalonitrile derivative by the action of potassium cyanide (93)…”

Aromatic Nucleophilic Substitution Reactions.

“…5,6-dinitrobenzonitrile(55,378). The numerous addition complexes formed by the solvated cyanide ion and aromatic compounds include XLV, XLVI, XLVII, XLVIII, and XLIX.…”

THE VON RICHTER REACTION1

“…(C) Hydrolysis of the nitrile yields a meia-substituted benzoic acid. 5 However, it has been reported by Blanksma (Beilstein, Erstes Erganzungswerk, X, p. 53) and by Lobry de Bruyn (12) that the nitro group in position 6 of 2-methoxy-5,6dinitrobenzonitrile is directly replaced by cyano in reaction with alcoholic potassium cyanide. Crucial to this mechanism is our postulate that only attack of cyanide ortho to a nitro group can result in the von Richter reaction.…”

“…Energy considerations make it improbable that hydride ion is actually set free in the transformation of VII into VIII; more likely there is intramolecular mi-6 Lobry de Bruyn (12) also believed that the point of entry of the cyano group was ortho to nitro; his mechanism for the von Richter reaction is in other respects quite different from gration with the hydrogen atom always more or less bonded to one carbon atom or the other. A similar case occurs in the rearrangement of phenylglyoxal to mandelic acid, for which tracer studies (16,17) indicate hydride ion migration from XI to XII to be the essential step.…”