Synthesis of pyrazolo[3,2‐ c ]‐1,2,4‐triazines from N ‐(5‐pyrazolyl)‐α‐ketohydrazidoyl halides
1985; Wiley; Volume: 22; Issue: 2 Linguagem: Inglês
10.1002/jhet.5570220249
ISSN1943-5193
AutoresAbdou O. Abdelhamid, Hamdi M. Hassaneen, Ahmad S. Shawali,
Tópico(s)Chemical Reaction Mechanisms
ResumoAbstract 3‐Phenylpyrazole‐5‐diazonium chloride (5) couples with benzenesulfonylacetone (9a) , benzenesulfonylacetophenone (9b) , ethyl benzenesulfonylacetate 9c , and ethyl benzoylacetate (12b) in ethanol in the presence of sodium acetate at room temperature to afford the pyrazolo[3,2‐ c ]‐1,2,4‐triazine derivatives 11a and 11b and the acyclic hydrazones 10c and 13 respectively. The products 11a,b and 10c can also be obtained from the reaction of the corresponding hydrazidoyl halides 8a‐c with sodium benzenesulfinate in high yield. The hydrazones 10c and 13 can be cyclised thermally or under the influence of acid into pyrazolo[3,2‐ c ]‐1,2,4‐triazine derivatives 11c and 14 respectively.
Referência(s)