Portal de Periódicos da CAPES

Studies on the synthesis of heterocyclic compounds. Part V. A novel synthesis of some pyridazin‐4‐(1 H )one derivatives and their reaction with hydrazine

1981; Wiley; Volume: 18; Issue: 2 Linguagem: Inglês

10.1002/jhet.5570180220

1943-5193

Salvatore Plescia, Giuseppe Daidone, Jole Fabra, V. SPRIO,

Synthesis and Reactivity of Heterocycles

Abstract Some phenylazo derivatives of β‐dicarbonyl compounds 1a,b,c,d reacted with dimethylformamide dimethylacetal to yield new 1‐phenyl‐3‐ R ‐4‐(1 H )pyridazinones 3a,e and 4. When compounds 3a and 3e were treated with hydrazine hydrate, they gave rise to pyrazolo[4,3‐ c ]pyridazines 5 and 7 , respectively. By the action of hydrazine hydrate on compound 4 , the 1‐phenyl‐3‐(1 H ‐pyrazol‐3‐yl)‐4‐(1 H )pyridazinone 8 was obtained. The structures of all the new compounds were assigned on the basis of satisfactory analytical and spectroscopic data.