A Selective and Mild Synthetic Route to Dialkyl Phosphates

Abstract

A very mild synthetic route to dialkyl phosphates is described. Reaction of the appropriate alcohol with PCl₃ followed by treatment with pyridine and CCl₄ afforded the corresponding trichloromethyl ester. Subsequent reaction with the triethylamine salt of acetic acid followed by hydrolysis of the formed mixed anhydride under very mild conditions afforded the dialkyl phosphates in high yield.

Key words

dialkyl phosphates - lipids - alcohols - dialkyl phosphonates - azobenzene

References

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10

Smits, E.; Wagenaar, A. unpublished results.

21

Due to the high solubility of diethyl phosphate in H₂O a lower isolated yield was obtained than expected. Continuous extraction will likely increase the yield considerably.

27

Diethyl phosphate is available from Supelco.