Butyl alkyl ketones, photolysis

Because di-/ fZ-alkyl peroxides are less susceptible to radical-induced decompositions, they are safer and more efficient radical generators than primary or secondary dialkyl peroxides. They are the preferred dialkyl peroxides for generating free radicals for commercial appHcations. Without reactive substrates present, di-/ fZ-alkyl peroxides decompose to generate alcohols, ketones, hydrocarbons, and minor amounts of ethers, epoxides, and carbon monoxide. Photolysis of di-/ fZ-butyl peroxide generates / fZ-butoxy radicals at low temperatures (75), whereas thermolysis at high temperatures generates methyl radicals by P-scission (44). 

Table 4.3. Quantum Yields of the Primary Processes in the Photolysis of Alkyl-t-butyl Ketones ...

The alkyl aryl ketone sensitised photolysis (313 nm) of hexane solutions of t-butyl Cl reported by HarrimaniZ also gave HCl as a major product together with 2-methyl propene. Quantum yields ranged from 0.19 when benzophenone was the sensitiser to 0.313 for EtC=0 and the involvement of the triplet state was confirmed by the quenching of the reaction by 2,5-dimethyl-hexa-... 

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