Matrix-Isolation Infrared Spectroscopy of Hydrogen-Bonded Complexes of Triethyl Phosphate with H2O, D2O, and Methanol

Abstract

The infrared spectra of adducts of triethyl phosphate (TEP) with H2O, D2O, and methanol (MeOH), isolated in a nitrogen matrix, are reported. A red shift in the phosphoryl (P=O) stretching vibration of triethyl phosphate was seen, which indicated adduct formation. Adducts of the type 1:1 and 1:2 of TEP…H2O and TEP…MeOH were identified in the matrix. It was observed that adduct formation occurred only with the phosphoryl oxygen and not with the alkoxy oxygen of triethyl phosphate. A red shift in the OH stretching vibration of water, as well as that of methanol, was also observed because of adduct formation. Solution spectra of TEP were also recorded in the same solvents and compared with the matrix spectra.