Theoretical calculations dioxiranes

X-Ray single crystal structural analysis was used to unambiguously establish the stmcture of 4 which is in reasonable agreement with results of B3LYP/6-31G(d) theoretical calculations. The crystals are found to be orthorhombic. Compared to that in the parent dioxirane 1, the 0-0 bond length in 4 (1.503 A) is shortened by 0.013 A while the CO bonds are found to be longer (1.414 A, and 1.388 A in la). 

Some of the reviews of dioxirane chemistry mentioned also contain summaries of theoretical calculations on dioxiranes theoretical aspects of peroxides contains a section on dioxiranes cited references for details of the theoretical calculations contained therein, some of the major conclusions, as well as some of the unreviewed data, are given here. 

In the past decade more efficient code and faster computers have allowed the use of electron-correlated methods of calculation and this has opened this area of theoretical chemistry to a wide range of research groups. The present sequel will be focused mainly on recent theoretical studies on a variety of oxidative processes involving oxygen atom transfer. We will include an extensive description of the very recent chemistry of peroxyni-trous acid (HO—ONO), dioxiranes, peracids and alkyl hydroperoxides. Since chemically realistic molecular systems can now be treated at an adequate level of electron-correlated... 

A recent theoretical study on the effect of substituents on the strain energies of small ring compounds has provided some valuable insight into the differences between 1,2-dioxetanes and 1,3-dioxetanes <2002JOC2588>. The C-H bonds within 1,2-dioxetane have been calculated to be stronger than those within 1,3-dioxetane by some 8 kcal mol-1 at the G2 level of theory. Calculations at the same level of theory indicate that 1,2-dioxetane is more strained than 1,3-dioxetane by some 6 kcal mol-1. Somewhat surprising is that this study has also shown that 1,2-dioxetanes are more strained than dioxiranes by some 7-12 kcal mol-1, which is in stark contrast to the case for the parent hydrocarbons and our expectations. The vibrational frequencies and the moments of inertia have also been calculated for the parent 1,2- and 1,3-dioxetanes <1997PGA2471>. 

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