Propionyl benzoyl peroxide

The CIDNP technique gives much useful information about diacyl peroxide decomposition. We shall discuss an example from the work of Ward, the decomposition of propionyl benzoyl peroxide (14), which in the presence of I2 yields the products in Equation 9.27.84 Figure 9.1 shows the proton magnetic resonance spectrum recorded while the reaction is occurring at 100°C. The first step... 

Figure 9.1 Spectrum recorded during the decomposition of a solution of propionyl benzoyl peroxide and iodine in o-dichlorobenzene at 100°C. The numbers in parentheses below the formulas indicate the relative spectrum amplitudes for the underlined protons. Spectrum groups referred to in the text are indicated at the top of the figure. Reprinted with permission from H. R. Ward, Accts. Chem. Res., 5, 18 (1972). Copyright by the American Chemical Society.

Pacansky, J., Gardini, G.P., and Bargon, J., Low temperature studies on propionyl benzoyl peroxide and propionyl peroxide. The ethyl radical, /. Am. Chem. Soc., 98, 2665, 1976. 

Szwarc and Smid (1986) suggested the possibility of intermolecular H bonding of the radicals from benzoyl peroxide to trifluoroacetic acid, in order to explain the different products from this reaction and that of the acid with propionyl peroxide. 

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