Über die Dicyanierung der 1,4‐Diaminoanthrachinone und die Reaktivität der 1,4‐Diamino‐9,10‐dihydroanthracen‐2,3‐dicarbonitrile gegenüber nucleophilen Reagenzien 3. Mitteilung über Arylierungen und Heterocyclisierungen von Anthrachinonsystemen

The Dicyanation of 1,4‐Diaminoanthraquinones and the Reactivity of 1,4‐Diamino‐9,10‐dioxo‐9,10‐dihydroanthracene‐2,3‐dicarbonitriles towards Nucleophilic Reagents The reaction of 1‐amino‐9, 10‐dioxo‐4‐phenylamino‐9,10‐dihydroanthracene‐2‐sulfonic acid ( 1 , RC 6 H 5 ) with cyanide in water yields a mixture of 1‐amino‐9,10‐dioxo‐4‐phenylamino‐9,10‐dihydroanthracene‐2‐carbonitrile ( 3 , R C 6 H 5 ) and 1‐amino‐4‐(phenylamino)anthraquinone ( 4 , R C 6 H 5 ) under the usual reaction conditions (Scheme 1) . In dimethylsulfoxide, however, a second cyano group is introduced, and 1‐amino‐9,10‐dioxo‐4‐phenylamino‐9,10‐dihydroanthracene‐2,3‐dicarbonitrile (7) is formed (Scheme 2) . The cyano groups are very reactive towards nucleophiles. The cyano group in 2‐position can be substituted by hydroxide and aliphatic amines (Schemes 5 and 6 ). The cyano group in 3‐position can be eliminated by aliphatic amines and hydrazine (Scheme 7) . Nucleophilic attack at the cyano C‐atom of the 2‐cyano group by suitable reagents leads to ring formation, yielding e.g. 2‐(Δ 2 ‐1, 3‐oxazolin‐2‐yl)‐, 2‐(benz[ d ]imidazol‐2‐yl)‐ and 2‐(1 H ‐tetrazol‐5‐yl)anthraquinones ( Schemes 8 and 10 ).