Hexaterphenylyl- and Hexaquaterphenylylben-zene: The Behavior of Chromophores and Electrophores in a Restricted Space

摘要

Oligo-para-phenylenes and poly-para-phenylenes are classical chromophores and redox systems. Because of their electroluminescent properties, they have been used often recently as active components in light-emitting diodes, but they can also be employed to investigate the influence of chain length and geometry on charging processes. For both applications, it would be desirable to have model compounds that contain several identical oligomer building blocks in a restricted space. We therefore directed our attention to the aesthetically appealing benzene derivatives hexa-p-terphenylylbenzene (1) and hexa-p-quaterphenylylbenzene (2). Formally, the star-shaped coinpound 1 can be regarded as being constructed of three septiphenyl chains with one benzene unit in common. However, the interplanar angle makes an arrangement of six electronically coupled terphenylyl chains a more plausible structure. We describe the synthesis and the electrophone and chromophoric properties of 1 and 2.