Characterization and optical properties of tetrapyrazinoporphyrazines with phenylene dendron group

The treatment of the ethynyl compound 3 with one equivalent of 3,4-bis-(4-methoxyphenyl)-2,5-diphenyl-cyclopenta-2,4-dienone in degassed p-xylene afforded the corresponding 2,3-dicyanopyrazine derivatives containing a phenylene dendron group (4). The absorption spectra of the tetrapyrazinoporphyrazinato copper complexes (5) with long alkyl groups dramatically changed due to molecular aggregation depending on the polarity of the solvent. The variation in their aggregation behaviors depending on the polarity of the solvent was well correlated with their chemical structures.