1979/01/15 by J. Peter Guthrie · 3 citations
Chemical Engineering · Chemistry · Environmental Science · #Chemical Reaction Mechanisms #Chemical and Physical Properties in Aqueous Solutions #Chemistry and Chemical Engineering
paper · pdf · doi:10.1139/v79-039
openalex publication_date 1979/01/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
From data in the literature the free energies of formation in aqueous solution of triethyl phosphite and diethyl phosphonate can be calculated as −138.4 ± 1.7 and −165.1 ± 2.0 kcal mol −1 , respectively. From these values, by application of free energy relations which we have published, the free energies of formation of the corresponding hydroxy compounds can be calculated and thence the equilibrium constants for tautomerization, which are 10 7.2 , 10 8.7 , and 10 10.3 in favor of the tetracoordinate phosphonate tautomer for P(OEt) 2 OH, P(OEt)(OH) 2 , and P(OH) 3 , respectively. Using estimated pK a values for the tricoordinate phosphite species the tautomerization equilibria for the anions could also be calculated, as could the pK a values from the P—H bonds: 13, 26, and 38 for H—PO(OEt) 2 , H—PO 2 (OEt) − , and H—PO 3 2− , respectively.