Light harvesting and energy transfer within coumarin‐labeled polymers

Linear copolymers that have pendant coumarin‐2 and coumarin‐343 chromophores were prepared as analogues to previously synthesized light‐harvesting dendrimers. The chromophore ratios within these polymers were maintained similar to those of the various generation dendrimers to investigate the effect of polymer architecture on the energy‐transfer efficiency between the coumarin‐2 donors and coumarin‐343 acceptors. Both physical and photophysical properties of these polymers were analyzed and compared to those of the analogous dendrimers. Energy‐transfer efficiencies were relatively high in the polymers; however, deleterious excimer formation between the coumarin‐343 chromophores diminished the quantum yield of fluorescence of the polymers when compared to the analogous dendrimers. Overall, it was found that the ultimate performance of the dendritic light‐harvesting antennae was superior to that of the polymeric analogues, but the polymers were more practical in terms of synthetic accessibility.