5-Fluoro-2-nitrophenylacetic acid → 5-fluoro-1,3-dihydro-2H-indol-2-one

Participants

Reaction Steps

A mixture of 24 g. of 5-fluoro-2-nitro-phenylacetic acid, 2.0 g. of platinum oxide (PtO2) and 250 ml. of glacial acid is hydrogenated at room temperature and 50 p.s.i. until the theoretical amount of hydrogen is taken up. The resulting mixture is filtered and the solvent evaporated off in vacuo. The residue is triturated with water and the resulting precipitate recrystallized from methylene chloride/diethyl ether to obtain 5-fluoro-oxindole, m.p. 131°-133° C.

Provenance & Evidence