Dimethyl methylphosphonate → Dimethyl 3-cyclohexyl-2-oxobutylphosphonate

Temperature

0 °C

74.5 g. of dimethyl methylphosphonate were dissolved in 514 ml. of tetrahydrofuran and the solution cooled to -60°C. To this solution a solution of n-butyl-lithium [prepared from 40.5 g. of n-butyl bromide and 9.2 g. of lithium] in 240 ml. of diethyl ether was added dropwise. A solution of 39.5 g. of ethyl 2-cyclohexylpropionate in 130 ml. of tetrahydrofuran was added dropwise and the mixture stirred at the same temperature for 2 hours and afterwards at 0°C. overnight. The reaction mixture was then neutralized to pH 7 with acetic acid, concentrated under reduced pressure and, after the addition of water to the residue, extracted with diethyl ether. After drying the ethereal extract, the solvent was distilled off and the residue subjected to distillation under reduced pressure to obtain 40 g. (yield 30.2 %) of the title compound as a colourless oil having the following physical characteristics:

1. concentrationconcentrated under reduced pressure
2. additionafter the addition of water to the residue
3. extractionextracted with diethyl ether
4. customAfter drying the ethereal
5. extractionextract
6. distillationthe solvent was distilled off
7. distillationthe residue subjected to distillation under reduced pressure
8. customto obtain 40 g

ORD record

ord-8caf455991bd442999f97627902fd15a

Source dataset

uspto-grants-1976_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US03978229