Ethyl 3-amino-2-cyclohexylpropyl(diethoxymethyl)phosphinate → 3-Amino-2-cyclohexylpropylphosphonous acid

A solution of 1.4 g of ethyl 3-amino-2-cyclohexylpropyl(diethoxymethyl)phosphinate in 30 ml of 36% aqueous hydrochloric acid is heated to reflux for a period of 1 hour. The reaction mixture is then allowed to cool to room temperature, concentrated under reduced pressure and co-evaporated twice with 10 ml of water under reduced pressure. The crude product is then dissolved in 20 ml of water washed twice with 20 ml of diethyl ether and the aqueous layer is then separated and evaporated under reduced pressure. The crude product is dissolved in 50 ml of dry ethanol and 5 ml of propylene oxide is added dropwise. The precipitated solid is collected by filtration and dried to give 3-amino-2-cyclohexylpropylphosphonous acid m.p. 235°-240° C., 31P=28.2 ppm (D2O).

1. temperatureto reflux for a period of 1 hour
2. concentrationconcentrated under reduced pressure
3. dissolutionThe crude product is then dissolved in 20 ml of water
4. washwashed twice with 20 ml of diethyl ether
5. customthe aqueous layer is then separated
6. customevaporated under reduced pressure
7. dissolutionThe crude product is dissolved in 50 ml of dry ethanol
8. addition5 ml of propylene oxide is added dropwise
9. filtrationThe precipitated solid is collected by filtration
10. customdried

ORD-Eintrag

ord-fad4500fb8784ea5980fcb81d8291339

Quelldatensatz

uspto-grants-1990_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04908465