Mechanism of Thermal Oxidation of the Benzimidazole System
Annual technical rept. Feb 1970-Jan 1971
WRIGHT STATE UNIV DAYTON OH DEPT OF CHEMISTRY
Pagination or Media Count:
In the report, experimental evidence is reported in support of the suggestion that pyrolytic oxidation of the PBI at high temperatures initiates at the carbocyclic aromatic ring adjacent to the imidazole nucleus. Solution oxidation of benzimidazole model compounds yielded corresponding 2- arylimidazole-4, 5-dicarboxylic acid oxidation products demonstrating that the 2-arylimidazole nucleus is more resistent to oxidation than the adjacent benzenoid nucleus. Subsequent oxidative pyrolysis of solution oxidation intermediates at 300C provided the same products oxides of carbon, aromatic nitriles and cyanogen obtained when the parent model compound is oxidatively pyrolyzed. Oxidative pyrolysis of carbon-13 labelled benzimidazole model was also carried out. These data were found to be consistent with the mechanism previously proposed for thermooxidative degradation of PBI.
- Organic Chemistry