Synthesis of the Perimidin-4- and -6-one systems

Abstract

A simple and efficient method has been devised for the synthesis of π- deficient perimidin-4- and -6-one systems, which were of interest in connection with their reactivity towards nucleophiles. The procedure entails successively, the conversion of substituted naphthalenes into 1,8-dinitro derivatives, reduction to 1,8-diamines, formation of perimidines and dihydroperimidines by treatment with carbonyl compounds, and finally oxidation with Fremy's salt. The course of oxidation was determined by the positions of the other substituents. A number of methyl- and chloro-substituted perimidin-4- and -6-ones have been identified.     Oxidation of the intermediate 1,8-diamines produced several new 5- amino-1,4-naphthoquinones as well as 8-amino-1,2-naphthoquinones. Simple derivatives of the latter system have not been previously reported.