Planar para-phenylene oligomers

Abstract

Planar, methylene-bridged quinque- and septiphenyl oligomers were synthesized as soluble, hitherto unknown compounds. The series of homologous and planar ladder-type oligophenyls (ter-, quinque-, septiphenyl) was characterized especially with respect to their optical properties (absorption and emission) as function of increasing chain length, and compared to the corresponding ladder-type polyphenylene. An effective conjugation length of about 12 benzene rings was determined within this series of planar oligo- and polyphenylenes.