Benzene → HCID 19880032, compound

Then, 87 g of 85% KOH was dissolved in 87 ml of water, and 100 g of the above ethyl 4-propoxy-2-ethoxycarbonylvalerate was added at 15°-25° C. in 45 min. The mixture was stirred at 90°-96° C. for 2 hours, and then cooled. While keeping the temperature below 20° C., a solution of 138 g of conc. sulfuric acid in 194 ml of water was added dropwise in 30 min. The mixture was stirred at 90°-95° C. for 3 hours, cooled to room temperature and then subjected to extraction with ether. The ether layer was washed with saturated saline water and then ether was distilled off, followed by vacuum distillation to obtain 47 g of a fraction of 100°-130° C./5 mmHg. Benzene was added to the fraction, and the mixture was washed with 5% NaOH aqueous solution. The aqueous layer was acidified to pH 1 with 6N-hydrochloric acid and subjected to extraction with ether. The ether extract was washed with saturated saline water, and ether was distilled off to obtain 38 g of 4-propoxyvaleric acid.

1. temperaturecooled
2. customthe temperature below 20° C.
3. stirringThe mixture was stirred at 90°-95° C. for 3 hours
4. extractionsubjected to extraction with ether
5. washThe ether layer was washed with saturated saline water
6. distillationether was distilled off
7. distillationfollowed by vacuum distillation
8. customto obtain 47 g of a fraction of 100°-130° C./5 mmHg
9. washthe mixture was washed with 5% NaOH aqueous solution
10. extractionsubjected to extraction with ether
11. extractionThe ether extract
12. washwas washed with saturated saline water, and ether
13. distillationwas distilled off

ORD record

ord-94e3dc45d49f4af0afd9319f3b33355c

Source dataset

uspto-grants-1992_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05143643