Synthesis of metal complexes of Bis- (1,2,6,7 -Tetracyano-3,5-diimino-3,5-dihydropyrrolyzinide)

摘要

A process is described for preparing the carbanion of the title as its sodium salt with quantitative yields and at a high level of purity, by a two-stage reaction between disodium-tetracyano-ethylene, Lewis acids and water. Metal complexes used as dyes in industrial applications are prepared from said carbanion.