Abstract: The compound 2-((1, 3-dimethyl-1 H-pyrazol-5-yl)(methyl) carbamoyl) benzene- diazonium hydrogen sulfate (10) was reacted with copper sulfate and sodium chloride, in the presence of ascorbic acid as reducing agent, to afford a mixture of the chlorinated epimers 4′-chloro-2, 2′, 5′-trimethyl-2′, 4′-dihydrospiro [isoindoline-1, 3′-pyrazol]-3-one (18) and (19), the epimers 4′-hydroxy-2, 2′, 5′-trimethyl-2′, 4′-dihydrospiro [isoindoline- ...
