Tetrahydrofuran → Dimethyl [2-oxo-2-(3-propylcyclopentyl)ethyl]phosphonate

17 ml. of a 2 M solution of n-butyllithium in diethyl ether were added dropwise with stirring, under an atmosphere of nitrogen, to a solution of 4.2 g. of dimethyl methylphosphonate in 40 ml. of dry tetrahydrofuran at -50° to -60° C. After stirring for 10 minutes, 2.9 g. of 1-methoxycarbonyl-3-propylcyclopentane in 10 ml. of dry tetrahydrofuran were added dropwise at -78° C. and the reaction mixture was stirred for 4 hours at -78° C. and further stirred overnight at 0° C. The reaction mixture was then acidified with acetic acid and concentrated under reduced pressure. The residue was diluted with diethyl ether, washed with water, dried over magnesium sulphate and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel using ethyl acetate as eluent to give 3.1 g. of the title compound having the following physical characteristics:

1. customat -50° to -60° C
2. stirringAfter stirring for 10 minutes
3. stirringthe reaction mixture was stirred for 4 hours at -78° C. and further stirred overnight at 0° C
4. concentrationconcentrated under reduced pressure
5. additionThe residue was diluted with diethyl ether
6. washwashed with water
7. dry with materialdried over magnesium sulphate
8. concentrationconcentrated under reduced pressure
9. customThe residue was purified by column chromatography on silica gel
10. customto give 3.1 g

ORD record

ord-0d4f9c43218a4c01a7d73292a9c50a41

Source dataset

uspto-grants-1979_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04180675