Hydrochloric Acid → 2-(Hydroxyimino)-3-(2-nitrophenyl)propanoic acid

Beteiligte Stoffe

Reaktionsschritte

Absolute ethanol (24,000 ml) and 3,240 g (60.0 moles) of sodium methoxide are charged into a 20 gallon reaction flask. The solution is stirred under nitrogen while a solution of 8228.4 g (60.0 moles) of o-nitrotoluene and 8768.4 g (60.0 moles) of diethyl oxalate is added all at once. The resulting solution is heated at reflux for 25 minutes, cooled to 60° with an ice-bath and 18,000 ml of water are cautiously added. Heat is then applied and the mixture is held at the reflux temperature for 1 hour. Most of the ethanol is then removed. The turbid solution is cooled at 50° and a solution of 4,140 g (59.6 moles) of hydroxylamine hydrochloride in 6,000 ml of water is added all at once. The temperature is maintained at 50°, the pH is adjusted to 7.0 with 6,000 ml of 10N sodium hydroxide solution and the reaction mixture stirred overnight at ambient temperature. The suspension is cooled to 10° and the pH is adjusted to 1.0 with 6,000 ml of 12N hydrochloric acid. The stirring is continued overnight at 10° to complete the liberation of the free acid. The solid is collected, washed with 6×4,000 ml of water, air dried overnight and suspended in 20,000 ml of toluene. The suspension is stirred for 1 hour under nitrogen atmosphere. The product is collected, washed with 4×2,000 ml of toluene followed by 4×2,000 ml of petroleum ether and dried (5 mm Hg/60°) to give 2-nitrophenylpyruvic acid oxime, m.p. 158°-60° (dec).

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