P,P,P′,P′-Tetraethyl P,P′-ethylidenebis[phosphonate] → HCID 13612965, compound

Participants

Reaction Steps

A solution of 13.29 g (40 mmol) of tetraethyl ethane-1,1-diphosphonate in 120 ml of dry tetrahydrofuran was cooled to -78° C. in an argon atmosphere followed by the addition of 24.24 ml (40 mmol) of a n-butyllithium hexane solution (1.65 mmol/ml) and stirring for 30 minutes. After adding a solution of 7.63 g (40 mmol) of 4-methylthiobenzenesulfenyl chloride in 50 ml of dry tetrahydrofuran to this mixture, the reaction mixture was allowed to warm up to room temperature followed by stirring for 3 hours. After pouring the resulting mixture into icewater, the mixture was extracted with ethyl acetate (3×150 ml). The solvent was distilled off under reduced pressure after the combined organic layer was washed with water and saturated brine and dried over anhydrous magnesium sulfate. A mixture of tetraethyl 1-methylthiophenyl)thio]ethane-1,1-diphosphonate and tetraethyl 1-chloroethane-1,1-diphosphonate was obtained as the residue. This mixture was then carefully purified with column chromatography (developing solvent: ethanol: ethyl acetate=5:95) to obtain 7.12 g of the target compound in the form of a yellow oily substance.

Provenance & Evidence