Luminescent π-conjugated polymers have received attention owing to their potential for application in organic light-emitting diodes. 1-4 Considerable work has been carried out on all organic polymers; however, less attention has been given to π-conjugated polymers that incorporate a transition metal complex chromophore into the polymer backbone. 5 This is surprising given that charge transfer excited states of d6 transition metal complexes have been studied extensively owing to their unique properties which include tunable excited state energies, moderately efficient luminescence, and diverse excited state redox reactivity. 6

We have initiated an effort to synthesize and characterize the excited state properties of soluble, π-conjugated polymers comprising the aryleneethynylene architecture which incorporate d6 transition metals chelated to a 2, 2′-bipyridyl site that is integral to the π-conjugated system. The present communication describes our initial findings on a series of polymers that contain the fac-(bpy) ReI (CO) 3Cl (bpy) 2, 2′-bipyridyl) chromophore. The Re (I) chromophore was selected because it features a welldefined Re f bpy metal to ligand charge transfer (MLCT) excited state that is long-lived, luminescent, and redox active. 7 Polymers A-D were synthesized from 1, 2, and 3 via Pdmediated cross coupling (Scheme 1). 3, 8-10 A-D vary in the mole ratio of 1 to 2 used in the coupling reaction mixtures, which ranged from 0: 1 (A) to 1: 1 (D). 8 FTIR spectra of B, C, and D confirm that the (bpy) ReI (CO) 3Cl unit is incorporated into the polymers by the appearance of the a′(1), a′′, and a′(2) carbonyl bands at 2024, 1930, and 1907 cm-1, respectively. 11 Quantitative analysis using the 2024 cm-1 IR absorption band indicates that the mole fraction of (bpy) ReI (CO) 3Cl containing