AbstractPhenacylmalononitriles2react with hydrazines, acetic‐hydrochloric acid and with diazotised primary aromatic amines to afford phenacylpyrazole (5a,b), aminofurans (6a,b) and aminopyrazole derivatives (3a,d) respectively. The synthesised derivatives (3d, 6a) were the key materials for the synthesis of isoindolinedione, (7a–c) pyrazolopyrimidine (9, 10), and pyrazolopyridazine derivatives (11). The structures of the newly synthesised heterocycles were established on the basis of elemental analyses and spectral data besides synthesis via other rou