Thermo- and photoinduced

As already mentioned, most interesting are the properties of the aziridines connected with cleavage of the C-C bond of the sterically strained three-membered cycle, namely, thermo- and photoinduced cycloaddition reactions. Photo- and thermochromism inherent to these compounds are also linked with the breaking of this bond in the literature. 

Dicyclohexadienones are relatively unstable and undergo thermo- and photoinduced reactions. Their formation in the course of inhibited oxidation of polymers may be considered as transient. The compounds formed by their successive transformations may be more likely identified in the stabilized substrate. 4,4 -Di-oxycyclohexadienones are cleaved already at temperatures below 100 °C128 under... 

The most studied type of reaction of aziridines is the transformations via a thermo- or photoinduced bipolar ylide. Among the numerous works related to this question are the reviews by Padwa [78] and Lown [79] the analysis of reactions of this type which do not involve the aziridine cycle are left out of this present work. 

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