Phenylhydrazine → 2-amino-benzoic acid N'-(2-fluoro-phenyl)-hydrazide

Participants

Reaction Steps

A phenylhydrazine b (e.g., 2-fluorophenylhydrazine) or pyridinylhydrazine (e.g., 2-hydrazinopyridine) that has been treated with or without a base such as N,N-diisopropylethylamine or triethylamine in a suitable solvent (e.g., ethanol or tetrahydrofuran (THF)) is reacted with the anhydride a (e.g., isatoic anhydride) to give the hydrazide c (e.g., 2-amino-benzoic acid N′-(2-fluoro-phenyl)-hydrazide). c is then acidified and reacted with sodium nitrite, followed by ethanol to generate the indazole d (e.g., 1-(2-fluoro-phenyl)-1H-indazol-3-ol).

Provenance & Evidence