Intrachain electron and energy transfer in conjugated organometallic oligomers and polymers

Article abstract of DOI:10.1002/chem.200800304

The synthesis of polymers of the type (-Cz-C≡C-PtL ₂-C≡C-Cz-X-)_n along with the corresponding model compounds (Ph-PtL′₂-C≡C-Cz)₂-X-, where Cz = 3.3′-carbazole, X = nothing, Cz, or F (2,2′-fluorene), L = PBu ₃, and L′ = PEt₃ are reported. The electronic spectra (absorption, excitation, emission, and ns-transient spectra) and the photophysics of these species in 2-methyltetrahyrofuran (2MeTHF) at 298 and 77 K are presented. Evidence for singlet electron and triplet energy transfer from the Cz chromophore to the F moiety are provided and discussed in detail. The rate for electron transfer is very fast (>4×10¹¹ s ^-1), whereas that for triplet-triplet energy transfer is much slower (≈ 10³s^-1). This work represents a very rare example of studies that address electronic communication in the backbone of a conjugated organometallic polymer.