Premium
Synthesis and some reactions of 4‐(ethoxycarbonyl)‐1,5‐diphenyl‐1 H ‐pyrazole‐3‐carboxylic acid
Author(s) -
Şener Ahmet,
Bildirici İshak,
Tozlu İsrafil,
Genç Hasan,
Arısoy Kadir
Publication year - 2007
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570440516
Subject(s) - chemistry , hydrazine (antidepressant) , pyrazole , hydrate , pyridazine , medicinal chemistry , nitrile , derivative (finance) , carboxylic acid , nucleophile , organic chemistry , anhydrous , amide , catalysis , chromatography , financial economics , economics
1,5‐Diphenyl‐1 H ‐pyrazole‐3,4‐dicarboxylic acid‐4‐ethyl ester 2 , obtained from the 4‐ethoxycarbonyl‐5‐phenyl‐2,3‐furandione 1 and N ‐benzylidene‐ N ′‐phenyl hydrazine, was converted via reactions of its acid chloride 3 with various alcohols or N‐nucleophiles into the corresponding ester 5 or amide derivatives 6 , respectively. In addition, 2 was decarboxylated to give ethyl 1,5‐diphenylpyrazole‐4‐carboxylate 4 . Nitrile 7 derivative of 2 was also obtained by dehydration of 6a in a mixture of SOCl 2 and DMF. While cyclocondensation reaction of 2 with hydrazine hydrate leads to the formation of pyrazolo[3,4‐ d ]pyridazine‐4,7‐dione 8 , the reaction of 3 with anhydrous hydrazine provided a new bis pyrazole derivative 9 .