Synthesis and chemical properties of new soluble aromatic polyketones with cross π-conjugated systems

New phosphorescent aromatic polyketones with a 9,9-dioctylfluorene copolymerizing unit (; Ar = p-phenylene (Polymer 1) or pyridine-2,5-diyl (Polymer 2); Flu = 9,9-dioctylfluorene-2,7-diyl) were prepared by organometallic polycondensation. Chemical properties of the polymers support a notion that the polymer has an expanded π-conjugated system through the cross π-conjugated –Ar–CO–Ar– unit. Polymer 1 was photoluminescent with an emission peak at about 430 nm and quantum yields of 10 and 21% at room temperature (r.t.) and 77 K, respectively. The light emission from Polymer 1 showed features of phosphorescence with long decay lifetimes of 0.22 and 0.53 s at r.t. and 77 K, respectively. Polymer 2 behaved similarly in light emission.