The reactions o f the solvated electron, the H atom, the OH radical and the superoxide radi cal anion with /-butylhydroperoxide (/-BuOOH) have been studied in aqueous solutions using y-radiolysis and pulse radiolysis to generate these radicals.The solvated electron reacts rapidly with r-BuOOH (k = 5 x 109 dm 3 m ol" 1 s~') yielding /-BuO ' and OH in a ratio o f 4:1. The yield o f r-BuO' has been determined by measuring its fragmentation product, acetone.The H atom reacts more slowly with r-BuOOH (k = 5x 107 dm 3 m o l-1 s"1). There is very little H-abstraction from the methyl and the hydroperoxyl groups (about 3%), the main reac tion again being the scission o f the hydroperoxyl function with a branching ratio /-BuO'/'OH o f about unity.The OH radical reacts with /-BuOOH considerably more slowly (k = 8 x 107 dm3 m o l" 1 s ' 1) than with /-butanol (k = 5 X 108 dm3 m o l-1 s"1) with an approximate preference o f 8:1 o f ab stracting a methyl hydrogen over a hydroperoxyl hydrogen atom. The carbon-centered radical undergoes y-cleavage (k ~ 102 s"1) thereby reforming an OH radical. The resulting chain reac tion is rather short (maximum yield G (2-methyl-1,2-epoxypropane), 26 x 10"7 mol / ' at low dose rate) due to H-abstraction at the hydroperoxyl function o f r-BuOOH by the OH radical.The superoxide radical anion also reacts with /-BuOOH by cleaving the hydroperoxyl func tion. Its reactivity is, however, rather low (k = 5 dm3 m ol" 1 s"1).

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