Propylene Oxide → HCID 86746443, compound

E-2-methylamino-4-methyl-5-phosphono-3-pentenoic acid (3) 20 ml of trimethylbromosilane are added dropwise at 20° within a period of 10 minutes under argon to a solution of 9.50 g of E-2-(N-methylformylamino)-4-methyl-5-diisopropylphosphono-3-pentenoic acidethyl ester in 40 ml of dry dichloromethane. After stirring at room temperature for 20 hours, 37 ml of ethanol are added dropwise within a period of 15 minutes, and the whole is stirred for a further 20 hours. Theclear reaction solution is then concentrated to dryness by evaporation in vacuo. The residue is concentrated by evaporation twice more in each case after the addition of 30 ml of toluene. 128 ml of 2N hydrochloric acid areadded to the resulting oil, and the mixture is stirred at a bath temperature of 85° for 16 hours. The reaction mixture is concentrated by evaporation in vacuo. Concentration by evaporation twice after the addition of ethanol/toluene 1:1 yields an oily residue, which isdissolved in 51 ml of ethanol and to which there is added dropwise a solution of 51 ml of propylene oxide in 51 ml of ethanol. The product obtained in crystalline form is filtered off after 2 hours and recrystallised from water/ethanol. In this manner there is obtained E-2-methylamino-4-methyl-5-phosphono-3-pentenoic acid, m.p. 239° (decomp.).

1. stirringthe whole is stirred for a further 20 hours
2. concentrationTheclear reaction solution is then concentrated to dryness by evaporation in vacuo
3. concentrationThe residue is concentrated by evaporation twice more in each case
4. additionafter the addition of 30 ml of toluene
5. stirringthe mixture is stirred at a bath temperature of 85° for 16 hours
6. concentrationThe reaction mixture is concentrated by evaporation in vacuo
7. concentrationConcentration
8. customby evaporation
9. additiontwice after the addition of ethanol/toluene 1:1
10. customyields an oily residue, which
11. customThe product obtained in crystalline form
12. filtrationis filtered off after 2 hours
13. customrecrystallised from water/ethanol

ORD record

ord-29c5934a383140f4abc1e918b671c4b9

Source dataset

uspto-grants-1991_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05051413