Preparation of new rigid backbone conjugated organic polymers with large fluorescence quantum yields

Palladium-catalyzed cross-coupling reactions between 5,5'-dibromo-2,2'-bipy ridine and substituted phenyldiacetylenes provide a novel family of rigid b ackbone conjugated polymers 4a, 4b. The weight-average molecular weight det ermined by GPC, polystyrene standards, (M) over bar(w), was 23 350 g.mol(-1 ) for 4a and 13 460 g.mol(-1) for 4b, with a polydispersity index of 2.7 an d 1.9, respectively The highly luminescent polymers exhibit excellent solub ility and can readily be processed into transparent films. The model compou nds 5 and 6 show a fluorescence quantum yield close to unity.