147670-98-2

Upstream product

• 103344-71-4 (Z)-4-(4-chlorophenyl)-2-hydroxy-4-oxobut-2-enoic acid 
• 2028-74-2 p-chlorobenzenediazonium chloride 
• 362623-40-3 4-(4-Chloro-phenyl)-3-[(4-chloro-phenyl)-hydrazono]-2,4-dioxo-butyric acid 

Downstream Products

• 188935-75-3 4-(4-Chloro-phenyl)-3-[(4-chloro-phenyl)-hydrazono]-2,4-dioxo-butyric acid methyl ester 

Relevant academic research and scientific papers

FIVE-MEMBERED 2,3-DIOXOHETEROCYCLES. XXIII. SYNTHESIS OF 1-ARYL-3-AROYL-4,5-DIHYDRO-4,5-PYRAZOLEDIONES AND THEIR REACTION WITH WATER AND ALCOHOLS

4-Aroyl-3-arylhydrazono-2,4-dioxobutyric acids were obtained by the azo coupling of aroylpyruvic acids with arenediazonium salts. Under the influence of thionyl chloride (benzene, 78 deg C, 1.5-4h) they undergo cyclization to 1-aryl-3-aroyl-4,5-dihydro-4,