Diisopropyl Ether → HCID 20335994, compound

Participants

Reaction Steps

To an ice-sodium chloride chilled stirring suspension of 46.34 g. (0.23 mole) of 4-amino-5-chloro-2-methoxybenzoic acid in 400 ml. of methylene chloride was added 23.23 g. (0.23 mole) of triethylamine. After the temperature had fallen to 0° C., 24.96 g. (0.23 mole) of ethyl chloroformate was added dropwise while maintaining a temperature of 0°-5° C. by ice bath cooling. The mixture was stirred at this temperature for 1 hour. To this was added dropwise at 0°-5° C. a solution of 32.26 g. (0.23 mole) of 1,2-diethyl-4-pyrazolidinamine in methylene chloride and stirring was continued for 0.5 hour at this temperature. The resulting mixture was washed with a dilute solution of sodium bicarbonate and the methylene chloride dried (sodium sulfate), filtered, and concentrated in vacuo. The residue was dissolved in 2-propanol, filtered, and made acidic to litmus by bubbling hydrogen chloride gas through the solution. The product was recrystallized from a mixture of ethanol, 2-propanol and isopropyl ether. A yield of 34.6 g. of product which melted at 182°-185° C. was obtained. To the filtrate was added additional isopropyl ether and after chilling, 15.35 g. of product which melted at 179°-185° C. was obtained. The combined yield was 49.95 g. (50%).

Provenance & Evidence