Hydrochloric Acid → Dimethyl(2-oxo-4-phenylbutyl)phosphonate

Participants

Reaction Conditions

Reaction Steps

A solution of dimethyl methylphosphonate (12.4 g., 0.1 mole) in dry tetrahydrofuran (75 ml.) is stirred, maintained under a nitrogen atmosphere, cooled to -50° C., and treated with a 2 N solution of n-butyl lithium in hexane (50 ml., 0.1 mole) added dropwise. Upon completing the addition, the reaction mixture is kept at -50° C. for 1/2 hour to ensure anion formation and then is treated with ethyl 3phenylpropionate (8.9 g., 0.05 mole) added dropwise at -50° C. After stirring for an additional 11/2 hours at -50° to -40° C., the reaction mixture is poured into ice water (250 ml.) providing a turbid solution which is acidified with 2 N hydrochloric acid and extracted with ethyl acetate (4 × 75 ml.). The combined organic extract is dried over sodium sulfate and filtered. Evaporation of the filtrate in vacuo at 40° to 50° C. leaves an oily residue which is distilled to provide the title compound as an oil (11.0 g., 86%), b.p. 148°-150° C./0.1 mm.

Provenance & Evidence