A theoretical approach to experimental nitration of phenyl and benzyl substituted pyridine- N-oxide derivatives

Abstract

Quantum chemical calculations of 2-, 3-, and 4-phenyl substituted pyridine- N-oxide derivatives revealed that 2- and 3-phenyl derivatives nitrate via free base mechanism. For 4-phenylpyridine- N-oxide, however, calculations imply conjugated acid mechanism for nitration. For 2- and 4-benzylpyridine- N-oxide molecules a conjugated acid mechanism were suggested in nitration process. Attempts to search a correlation between the experimental acidity constants, p K a, and computed acidity constants were successful.