SPECTROFLUORIMETRIC INVESTIGATION OF 2-BENZOPYRYLIUM PERCHLORATES

Abstract

1,3-Dimethyl-6,7-dimethoxy-2-benzopyrylium perchlorate (1) and its 1-substituted-vinyl, 1-styryl, 1-substituted-styryl derivatives were prepared. The fluorescence properties of fifteen compounds were investigated by pectrofluorimetric method. The 1 and the 1-(substituted-vinyl) derivatives fluoresce intensely. The 1-(3-indolybvinyl)-3-methyl-6,7-dimethoxy-2-benzopyrylium perchlorate (14) shows the most intense fluorescence. The 1-styryl-3-methyl-6,7-dimethoxy-2-benzopyrylium perchlorate (4) fluoresces very weakly. The position of the substituent on the benzene ring and the quality of the substituent have an important influence on the fluorescence. Some investigated derivatives show intensive flourescence in the IR-region. Spectrofluorimetric methods were developed for the determination of eight compounds.