Ethyl 2,3-dioxobutanoate-2-arylhydrazones 1 on treatment with [hydroxy(tosyloxy)iodo]benzene 2 at reflux temperature and followed by heating in the presence of N-ethyldiisopropylamine afforded the cyclized ethyl 1-aryl-4-hydroxy-1H-3-pyrazolecarboxylates 4 in good yield.
No takes yet. Share an insight, caveat, or question.
Patel et al. (1991) studied this question.
Synapse has enriched 4 closely related papers on similar clinical questions. Consider them for comparative context: