Thermal acetyl peroxide

The thermal decomposition of diacyl peroxides has been the most frequently employed process for the generation of alkyl radicals. The rate and products of the unimolecular decomposition of acetyl peroxide have been the subject of many studies. Acetyl peroxide decomposes at a convenient rate at 70-80°C both in the solution and in the gas... 

The methoxy group of methyl acetate formed during the thermal decomposition of acetyl peroxide appears as an emission, whereas methyl chloride shows enhanced absorption. Consider the reaction sequence in equation (40). 

In this section, several typical CINPD spectra will be shown. These spectra can be explained by Kaptain s rules. Typical net absorptive and emissive CINDP signals were observed during the thermal decomposition of acetyl peroxide (AP) in hexachloroacetone at 110 °C as shown in Fig. 4-8. Here, enhanced absorptive signals were observed for CH3CI and CH4 and emissive ones for CH3COOCH3 and CH3-CH3. 

Fig. 4-8. 60 MHz H-CIDNP spectrum of the thermal decomposition of acetyl peroxide in hexachloroacetone. (Reproduced from Ref. [8] by permission from Kluwer Academic Publishers)...

Problem 4.1. Prove the enhanced absorptive CIDNP observed for CH3CI and CH4 during the thermal decomposition of acetyl peroxide (AP) in hexachloroacetone. 

Thermal decomp, of acetyl peroxide Study of cage effects i-CgH,8... 

In 19U8 Kharasch, McBay, and Urry (20) found that the reaction of aliphatic ketones with acetyl peroxide, at temperatures where the latter undergoes thermal decomposition, provided a convenient synthetic route to l,i -diketones. 

Acyltetramic acids (39) are almost completely enolized in solution as well as in the crystalline state [80JCS(P1)1057], whereby the exo-enol form (a) is favored. Irradiation of 39a in peroxide-free cyclohexene leads to [2 + 2]-cycloaddition at the exocyclic double bond. Subsequent thermal reaction opens the four-membered ring of cycloadduct 59. 3-(2-Acetyl-cyclohexyl)-l,5,5-trimethyl-2,4-pyrrolidinedione 60 is obtained in 85% yield. In solution, 60 establishes an equilibrium with cyclic hemiacetal 61 (92M93). (See Fig. 28.)... 

Perhydroxyl radical, 75 thermal generation from PNA of, 75 Peroxy radical generation, 75 Peroxide crystal photoinitiated reactions, 310 acetyl benzoyl peroxide (ABP), 311 radical pairs in, 311, 313 stress generated in, 313 diundecanyl peroxide (UP), 313 derivatives of, 317 EPR reaction scheme for, 313 IR reaction scheme for, 316 zero field splitting of, 313 Peorxyacetyl nitrate (PAN), 71, 96 CH3C(0)00 radical from, 96 ethane oxidation formation of, 96 IR spectroscopy detection of, 71, 96 perhydroxyl radical formation of, 96 synthesis of, 97 Peroxyalkyl nitrates, 83 IR absorption spectra of, 83 preparation of, 85 Peroxymethyl reactions, 82 Photochemical mechanisms in crystals, 283 atomic trajectories in, 283 Beer s law and, 294 bimolecular processes in, 291 concepts of, 283... 

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