Ethanol → HCID 22811228, compound

Diethyl 3-(N-ethoxycarbonyl-N-ethoxycarbonyloxyamino)-2(R)-hydroxypropylphosphonate (13.8 g) was dissolved in dichloromethane (25 ml). To the solution was added trimethylbromosilane (25 g) under ice-cooling. The reaction mixture was stirred at the same temperature for 30 minutes and at ambient temperature for 1.5 hours. Subsequently, the resultant mixture was concentrated under reduced pressure to give a residue, which is dissolved in water (50 ml). The aqueous solution was stirred at ambient temperature for an hour, washed three times with chloroform (20 ml) and then the aqueous layer was separated. After 1 N hydrochloric acid (140 ml) was added to the aqueous layer, the mixture was heated to reflux for 15 hours. The resultant mixture was concentrated under reduced pressure to give a residue, which was dissolved in a mixture of water (10 ml) and methanol (20 ml). The solution was adjusted to pH 3-4 with propyleneoxide (20 ml) and ethanol (200 ml) was added to the solution to precipitate an oil, which was separated by decantation, washed with ethanol (20 ml) and dissolved in water (20 ml). After the aqueous solution was treated with activated charcoal (100 ml), the activated charcoal was removed by filtration. The filtrate was evaporated to dryness under reduced pressure and dried over phosphorus pentoxide to give powdery 2(R)-hydroxy-3-(N-hydroxyamino)propylphosphonic acid (1.15 g).

1. temperaturecooling
2. concentrationSubsequently, the resultant mixture was concentrated under reduced pressure
3. customto give a residue, which
4. stirringThe aqueous solution was stirred at ambient temperature for an hour
5. washwashed three times with chloroform (20 ml)
6. customthe aqueous layer was separated
7. additionAfter 1 N hydrochloric acid (140 ml) was added to the aqueous layer
8. temperaturethe mixture was heated
9. temperatureto reflux for 15 hours
10. concentrationThe resultant mixture was concentrated under reduced pressure
11. customto give a residue, which
12. additionwas added to the solution
13. customto precipitate an oil, which
14. customwas separated by decantation
15. washwashed with ethanol (20 ml)
16. dissolutiondissolved in water (20 ml)
17. additionAfter the aqueous solution was treated with activated charcoal (100 ml)
18. customthe activated charcoal was removed by filtration
19. customThe filtrate was evaporated to dryness under reduced pressure
20. dry with materialdried over phosphorus pentoxide

ORD record

ord-db5ae9e6c2ef4800a497dbebd81560d1

Source dataset

uspto-grants-1980_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04206156