ChemInform Abstract: The Production of the Superoxide Radical Anion by the OH Radical-Induced Oxidation of Trimethylamine in Oxygenated Aqueous Solution. The Kinetics of the Hydrolysis of (Hydroxymethyl)dimethylamine

ChemInform ◽  
1987 ◽  
Vol 18 (25) ◽  
Author(s):  
S. DAS ◽  
M. N. SCHUCHMANN ◽  
H.-P. SCHUCHMANN ◽  
C. VON SONNTAG
Keyword(s):  
Aqueous Solution ◽  
Radical Anion ◽  
Superoxide Radical ◽  
Oh Radical ◽  
Superoxide Radical Anion ◽  
Kinetics Of ◽  
Hydrolysis Of

Radiolysis of Tertiary Butyl Hydroperoxide in Aqueous Solution. Reductive Cleavage by the Solvated Electron, the Hydrogen Atom, and, in Particular, the Superoxide Radical Anion

1990 ◽  
Vol 45 (10) ◽  
pp. 1425-1432 ◽  
Author(s):  
Shailesh Phulkar ◽  
Balijepalli Sethu Madhava Rao ◽  
Heinz-Peter Schuchmann ◽  
Clemens von Sonntag
Keyword(s):  
Hydrogen Atom ◽  
Radical Anion ◽  
Superoxide Radical ◽  
Maximum Yield ◽  
Branching Ratio ◽  
Main Reaction ◽  
Oh Radical ◽  
Solvated Electron ◽  
Tertiary Butyl ◽  
Superoxide Radical Anion

The reactions of the solvated electron, the H atom, the OH radical and the superoxide radical anion with t-butylhydroperoxide (t-BuOOH) have been studied in aqueous solutions using γ-radiolysis and pulse radiolysis to generate these radicals.The solvated electron reacts rapidly with t-BuOOH (k=5 × 109dm3mol-1 s-1) yielding t-BuO· and ·OH in a ratio of 4:1. The yield of t-BuO· has been determined by measuring its fragmentation product, acetone.The H atom reacts more slowly with t-BuOOH (k=5 × 10 7 dm3 mol-1 s-1). There is very little H-abstraction from the methyl and the hydroperoxyl groups (about 3%), the main reaction again being the scission of the hydroperoxyl function with a branching ratio t-BuO·/·OH of about unity.The OH radical reacts with t-BuOOH considerably more slowly (k=8 × 10 7 dm3 mol-1 s-1) than with t-butanol (k=5 × 108 dm3 mol-1 s-1) with an approximate preference of 8:1 of abstracting a methyl hydrogen over a hydroperoxyl hydrogen atom. The carbon-centered radical undergoes γ-cleavage (k ≈ 102 s-1) thereby reforming an OH radical. The resulting chain reaction is rather short (maximum yield G(2-methyl-1,2-epoxypropane), 26 × 10-7 mol J-1 at low dose rate) due to H-abstraction at the hydroperoxyl function of t-BuOOH by the OH radical.The superoxide radical anion also reacts with t-BuOOH by cleaving the hydroperoxyl function. Its reactivity is, however, rather low (k=5 dm3 mol-1 s-1)

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