Methanol → Phthalic Acid

Temperature

20 °C

To a solution of ammonium acetate (73.7 g) in methanol (250 ml) were added 2-(1-ethoxycarbonyl-1-methylethoxyimino)propanedinitrile (50.0 g) and 28% ammonia water (33.3 ml) at room temperature. After stirring for 15 hours at 20° C., potassium carbonate (33.0 g) was added to the solution, and the solution was evaporated under reduced pressure. A mixture of water (130 ml) and methylene chloride (110 ml) was added into the residue. The mixture was adjusted to pH 8.0-8.2 and extracted with methylene chloride twice. Phthalic acid (35.7 g) was added to the extract at 20°-30° C., and then diisopropyl ether (200 ml) was added thereto. After stirring for 2 hours at the same temperature, the resulting precipitate was collected by filtration, washed with diisopropyl ether (40 ml) and dried under reduced pressure to give phthalic acid salt (61.4 g) of 2-cyano-2-(1-ethoxycarbonyl-1-methylethoxyimino)acetamidine.

1. customthe solution was evaporated under reduced pressure
2. additionA mixture of water (130 ml) and methylene chloride (110 ml)
3. additionwas added into the residue
4. extractionextracted with methylene chloride twice
5. additionPhthalic acid (35.7 g) was added to the
6. extractionextract at 20°-30° C.
7. additiondiisopropyl ether (200 ml) was added
8. stirringAfter stirring for 2 hours at the same temperature
9. filtrationthe resulting precipitate was collected by filtration
10. washwashed with diisopropyl ether (40 ml)
11. customdried under reduced pressure

ORD record

ord-46aacdd729ba4f5dbbad80c1528b3ae2

Source dataset

uspto-grants-1992_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05162520