Torsion angles, hydroperoxides

TOCO see Thiol-olefin co-oxygenation Tocopherols, TEARS assay, 668 Torsion angles, hydroperoxides, 690 Tosylhydrazones, superoxide reactions, 1036 Total hydroperoxides see Peroxide value Total oxidative capacity, titration methods, 674 Total polar phenols, colorimetry, 664 Toxicity... 

The torsion angle R—O—O—H in alkyl hydroperoxides lies in the range of 100 20°, which is comparable to the value for H2O2, either in the gas phase or in the solid state (Tables 1 and 2) . In peroxides of the type R —O—O—(for R, R = alkyl, aryl, vinyl, alkynyl) a progressive increase of the peroxide dihedral angle with the steric demand of R and R is observed (Table 2). 

Potential barriers versus torsion angle for internal rotation are calculated for the following hydroperoxides and their corresponding methylperoxides ... 

A potential energy diagram for internal rotation versus Cb—OOH torsion angle in DBFOOH is shown in Figure 7.3 (Cb Cbenzene bond)- The data show three-fold, potentials with barriers near 3.6 kcal mof. This barrier is comparable to those obtained for the vinyl hydroperoxide species reported in chapter 3. The same rotational barrier in the Cb—00 of the corresponding radical DBF—00 is however, higher by 1.3 kcal mof. The radical DBFOO shows a two-fold symmetry with a barrier to be found at 4.9 kcal mof (Figure 7.4). 

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