In a
2-l. round-bottomed flask are placed
88 g. (0.75 mole) of o-tolunitrile (Org. Syn. Coll. Vol. I, 1941, 514),
300 cc. (2.6 moles) of 30 per cent hydrogen peroxide,
400 cc. of 95 per cent alcohol, and
30 cc. of 6 N sodium hydroxide solution (Note
1). The mixture evolves
oxygen and soon warms up owing to the heat of reaction; the temperature is kept at 40–50° by external cooling (Note
2). After about one hour, heat is no longer evolved; the temperature is then maintained at 50° by external heating for an additional three hours. The mixture, while still warm, is made exactly neutral to litmus with
5 per cent sulfuric acid and distilled with steam until 1 l. of distillate is collected. The residue, which has a volume of about 600 cc. (Note
3), is poured while hot into a
1-l. beaker and cooled to 20°. The crystals which form are filtered with suction. They are transferred to a
mortar and ground to a paste with 100 cc. of cold water, filtered again, and then washed on the filter with an additional 100 cc. of cold water. The
o-toluamide is obtained in the form of white crystals melting at
141–141.5°. The yield of air-dried product is
91–93 g. (
90–92 per cent of the theoretical amount) (Note
4). The product may be recrystallized from water (10 g. per 100 cc.). The recovery is
92 per cent, and the melting point is not changed (Note
5).