Propylene Oxide → 3-Aminopropyl(propargyl)-phosphinic acid

A suspension of 1,23 g (10 mmol) of 3-aminopropylphosphonous acid in 10.4 ml (50 mmol) of hexamethyldisilazane is heated to reflux under argon for 24 hours. 5 ml of diethylene glycol dimethyl ether are added to the clear solution obtained and the mixture is heated for additional 2 hours and then cooled to 0°. 8.5 ml (50 mmol) of N-ethyl-N,N-diisopropyl-amine are added, followed by slow addition of 3.8 ml (50 mmol) of propargyl bromide over a period of 40 minutes. The mixture is stirred for 1 hour at 0° and 4 hours at room temperature, filtered and evaporated under high vacuum. The residue is dissolved in 10 ml of dichloromethane and extracted with 3×10 ml of 1N hydrochloric acid solution. The water layer is evaporated under high vacuum and the residue obtained dissolved in 4 ml of methanol at 0°. 20 ml of propylene oxide are added during a period of 1 hour, after which time a crude product precipitates. Chromatography (silicagel Merck 230-400 ASTM, methanol) followed by recrystallization (methanol/ether) yields 3-aminopropyl(propargyl)-phosphinic acid, m.p. 172°-173°.

1. temperatureis heated
2. temperatureto reflux under argon for 24 hours
3. customobtained
4. temperaturethe mixture is heated for additional 2 hours
5. temperaturecooled to 0°
6. filtrationfiltered
7. customevaporated under high vacuum
8. dissolutionThe residue is dissolved in 10 ml of dichloromethane
9. extractionextracted with 3×10 ml of 1N hydrochloric acid solution
10. customThe water layer is evaporated under high vacuum
11. customthe residue obtained
12. customafter which time a crude product precipitates
13. customChromatography (silicagel Merck 230-400 ASTM, methanol) followed by recrystallization (methanol/ether)

ORD record

ord-251997364542409bb36ef3e937e25526

Source dataset

uspto-grants-1993_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05190933