Synthesis and Structure of Salts Derived from 6,8-Dialkoxy-1,3,7-Triazapyrenes

Abstract

Despite advances in the chemistry of azines, azoles, and their condensed analogs, the peri-annelated azaheteroaromatic systems have not been adequately studied. One such system, 1,3,7-triazapyrene, is the subject of the present study. A summary of previous work indicates that the specific fusion of the carbocyclic and heterocyclic rings in this molecule accounts for its special chemical properties. In our previous work, we reported the oxidative nucleophilic alkoxylation of 1,3,7-triazapyrenes, which is unusual among azines but proceeds readily under both base [1] and acid catalysis conditions [2]. The reaction of 1,3,7-triazapyrenes 1a,b with absolute primary alcohols saturated with dry hydrogen chloride proceeds through acid catalysis at room temperature in the presence of excess of K3Fe(CN)6 to give 6,8-dialkoxy-1,3,7-triazapyrenes 2a-d in 73-90% yields.