Enthalpies of formation of cyclic alkyl peroxides: dioxirane, 1,2-dioxetane, 1,2-dioxolane, and 1,2-dioxane

Enthalpies of formation of four cyclic alkyl peroxides are calculated using ab initio methods. The values are reported as: Δ H°f298(dioxirane) = −2.91 ± 1.34 kcal/mol, Δ H°f298(1,2-dioxetane) = 1.09 ± 0.51, Δ H°f298(1,2-dioxolane) = −27.43 ± 0.91 kcal/mol, and Δ H°f298(1,2-dioxane) = −31.74 ± 0.96 kcal/mol. Enthalpies of formation for 1,2-dioxetane, 1,2-dioxolane, and 1,2-dioxane are calculated using isodesmic reactions at the MP4SDTQ/6-31G∗ ∗ //MP2/6-31G∗ level of theory. These isodesmic reactions are ‘group balanced’. For dioxirane, reaction energies of two reactions are calculated using the G2 method. The difference of Δ H°f298(dioxirane) values determined using these two reactions is within 0.7 kcal/mol. Ring strain energies (in kcal mol−1) are determined as 30.7, 26.7, 7.3, 4.0 for dioxirane, 1,2-dioxetane, 1,2-dioxolane, and 1,2-dioxane, respectively. Comparisons are also made with a scaled PM3 estimation, and results are in reasonable agreement with the recommended values.