Peroxides rearrangements

The question of rearrangement in acyloxy radicals is still unsettled. In the case of the decomposition of -methoxy- -nitrobenzoyl peroxide rearrangement is observed, but the other circumstances indicate a polar mechanism for the reaction.118... 

Another BMS example, shown in Scheme 11.14, uses a cumene peroxide rearrangement to prepare 6-hydroxy-5-methyl-3H-pyrrolo[2,l-f [l,2,4]triazin-4-one, an intermediate for protein kinase inhibitors (brivanib). The terhary alcohol is converted to the hydroperoxide in situ with H2O2 and reacted with aqueous meth-anesulfonic acid as a catalyst to cause rearrangement [31]. 

Hydrogen atoms in allylic position are favorite sites for hydroperoxidation of chains. So, this mechanism proceeds in the formation of lateral hydroperoxides, and not like for other polymers, in intramolecular peroxides. Rearrangement of chemical structures coming from ozonides are rapidly observed (Scheme 33). 

This e c o-peroxide rearranged readily to form the /ra s-benzene trioxide 144 and gave trans-benzene dioxide 142 upon reaction with triphenylphosphite. A similar addition reaction occurred between singlet oxygen and indan 8,9-oxide 7 to yield a further endo-peroxide. An endo-peroxide adduct of an oxepin was also formed when singlet oxygen reacted with 1-benzoxepin 100. Upon deoxygenation with trimethylphosphite, the latter peroxide yielded an aldehyde. ... 

The chemistry displayed by the dioxygenases is not unique to these enzymes. The proposed mechanism involves an oxygenation of the catechol ring and subsequent decomposition of the resulting peroxide via a peroxide rearrangement or a dioxetane intermediate. All these steps have parallels in organic chemistry. 

The conversion of the peroxide intermediate to product can occur via either a peroxide rearrangement or a dioxetane species and there is still no agreement as to what the mechanism is in analogous organic reactions. 

Carboxy-inversion reaction. Denney and Sherman found that m-chloroperbenzoic acid (2) reacts readily with a carboxylic acid chloride (1) in hexane solution at 0 in the presence of pyridine to form a mixed peroxide (3). When the mixture is stirred for several hours at room temperature the peroxide rearranges to the mixed carbonate... 

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