1-Methoxyethanol → 1-Methyl-7-benzoyloxindole

Participants

Reaction Steps

A solution of 46 grams (0.17 mol) of 3-chloro-1-methyl-7-benzoylindole in 250 ml of methoxy-ethanol and 60 ml of 70% phosphoric acid was heated at reflux under a nitrogen atmosphere for 5 hours. The solution was then cooled and diluted with 1.5 liters of water. The organic materials were extracted with methylene chloride and concentrated. The concentrated extract was chromatographed on silica gel and the product eluted with isopropyl ether. The residue obtained crystallized upon standing and was recrystallized from isopropyl alcohol to give 8.9 grams of 1-methyl-7-benzoylindolin-2-one, having a m.p. of 89°-90.5° C.

Provenance & Evidence