Sodium Hydroxide → HCID 86708819, compound

Temperature

5 °C

Under a nitrogen atmosphere, into a reaction vessel were charged 15.00 g (138.7 mmol) of 1,4-phenylenediamine and 255 ml of tetrahydrofuran. A solution prepared by dissolving 9.07 g (92.5 mmol) of maleic anhydride in 45 ml of tetrahydrofuran was dropped into this under cooling with ice over a period of about 3 hours, then, the mixture was stirred at room temperature overnight. After completion of the reaction, the deposited crystal was isolated by filtration, washed with 30 ml of tetrahydrofuran, and dried at 40° C. to obtain 18.14 g of coarse (2Z)-4-[(4-aminophenyl)amino]-4-oxo-2-butenoic acid as an orange powder. To 18.14 g of coarse (2Z)-4-[(4-aminophenyl)amino]-4-oxo-2-butenoic acid was added 36 ml of water and the mixture was cooled to 0 to 10° C., and 17.59 ml of a 5N sodium hydroxide aqueous solution was dropped. Thereafter, the solvent was distilled off under reduced pressure to obtain a residue to which 270 ml of ethanol was added, and the mixture was stirred at 70° C. for 1 hour, cooled down to room temperature, then, the solid was filtrated and washed twice with 25 ml of methanol. The resultant solid was dried at 45° C. for 2 hours, to obtain 16.2 g of sodium (2Z)-4-[(4-aminophenyl)amino]-4-oxo-2-butenoate as a pale brown-white powder. Yield: 76.8%

1. distillationThereafter, the solvent was distilled off under reduced pressure
2. customto obtain a residue to which 270 ml of ethanol
3. additionwas added
4. temperaturecooled down to room temperature
5. filtrationthe solid was filtrated
6. washwashed twice with 25 ml of methanol
7. customThe resultant solid was dried at 45° C. for 2 hours

ORD record

ord-9bc5953c23fe43328e7a002614c3d5e1

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09068055B2