SYNTHESIS OF FUSED PERIMIDINIUM DERIVATIVES AND INVESTIGATION OF THEIR STRUCTURE BY AB INITIO CALCULATIONS

摘要

A series of perimidinium salts have been prepared by N-alkylation and N-amination methods. These salts were condensed with 1,2-dicarbonyl compounds and quinones (Westphal condensation) to produce pyridazino[2,3-a]perimidinium and, in one case, pyrido[2,3-a]perimidinium derivatives. Two of these heteroaromatic cations were studied by ab initio calculations at the SCF (self-consistent field) level using different basis sets. From Mulliken population analysis and geometrical considerations, it is predicted that the pyrrole-like nitrogen of the perimidinium moiety is lying out of the planarity, thus reducing the interaction with the fused pyridazinium ring. [References: 43]