Radiation-induced homolytic aromatic substitution. V. Effect of metal ions on the hydroxylation of toluene
The radiation-induced hydroxylation of toluene was investigated in presence of K$sub 2$Cr$sub 2$$O$$sub 7$, K$sub 3$Fe(CN)$sub 6$, K$sub 4$Fe(CN)$sub 6$, Fe(ClO$sub 4$$)$$sub 3$, Fe(NH$sub 4$)(SO$sub 4$$)$$sub 2$, CuSO$sub 4$, Cu(ClO$sub 4$$)$$sub 2$, and Cu(OCOCH$sub 3$$)$$sub 2$. With K$sub 2$Cr$sub 2$$O$$sub 7$, K$sub 3$Fe(CN)$sub 6$, and the Cu$sup 2+$ salts high conversions of the OH radicals to cresols were obtained. In all these cases the isomer distribution obtained at the highest concentration investigated (5 x 10$sup -2$ M) was the same 49 to 52 percent ortho, 22 to 24 percent meta, and 26 to 28 percent para). With the exception of K$sub 3$Fe(CN)$sub 6$ the percentage of G(m-cresol) increased with increasing concentration of metal salt. The pH had a marked effect on the formation of cresols due to the competing acid-catalyzed elimination of water from the initially formed hydroxymethylcyclohexadienyl radicals to give benzyl radicals. No reduction of the hydroxymethylcyclohexadienyl radicals by Fe(CN)$sub 6$$sup 4-$ was observed. For the rate of oxidation of the hydroxymethylcyclohexadienyl radicals the following sequence was established: Fe(CN)$sub 6$$sup 3-$ greater than Cu$sup 2+$ greater than Fe$sup 3+$.
- Research Organization:
- Puerto Rico Nuclear Center, San Juan
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-33-019739
- OSTI ID:
- 4097801
- Journal Information:
- J. Phys. Chem., v. 79, no. 18, pp. 1917-1920, Journal Name: J. Phys. Chem., v. 79, no. 18, pp. 1917-1920; ISSN JPCHA
- Country of Publication:
- United States
- Language:
- English
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