Ao. Abdelhamid et al., Reactions with hydrazonoyl halides. 31. Synthesis of some new pyrrolidino[3 4-c]pyrazolines, pyrazoles, and pyrazolo[3,4-d]pyridazines, MOLECULES, 5(7), 2000, pp. 967-973
Pyrrolidino[3,4-c]pyrazoline and pyrazole derivatives were synthesized via
reactions of a substituted hydrazonoyl bromide with N-arylmaleimides and ac
tive methylene reagents, respectively. Synthesized pyrazoles were reacted w
ith hydrazine hydrate to give the corresponding pyrazolo[3,4-d]pyridazines.