A Highly Fluorescent sigma-Bonded Platinum(II) Diketopyrrolopyrrole Complex

A sigma-bonded platinum(II) diketopyrrolopyrrole (Pt-DPP) complex was synthesized from a reaction of p-pinacolatoborylphenyl-substituted DPP with dichloro(1,5-cyclooctadiene)platinum(II), followed by a ligand exchange reaction with triphenylphosphine. The Pt-DPP complex is highly fluorescent not only in solution but also in the solid state. From the comparison of the emission properties with those of N-benzyl-DPPs bearing phenyl and p-bromophenyl substituents, the intense emission of the Pt-DPP complex is ascribed to the DPP-centered fluorescence. In the solid state, aggregation-caused quenching is mitigated by the well-segregated molecular packing due to the bulky triphenylphosphine ligands. The facile synthesis and unique fluorescence properties of the Pt-DPP complex are beneficial for creating DPP-based functional chromophores.