Condensations between diaminomaleonitrile (DAMN) and ketones in phosphorus pentoxide- ethanol gave the open-chain adducts. Aromatic a-ketones and acyl cyanides gave the Schiff bases (1 and 5), several of which were converted to alkyl DAMN (3 and 7), addition product with methyl vinyl ketone (4), and pyrazine derivatives (6 and 8). The condensation with P- keto esters and with &diketones gave another type of adducts, enamines (9 and 12), ...
