Synthesis and characterization of organoboron quinolate polymers with tunable luminescence properties

A modular one-pot approach for the synthesis of well-defined organoboron quinolate polymers and the tuning of their photoluminescence is reported. Highly selective borylation of poly(4-trimethylsilylstyrene) ( PSSiMe3) followed by replacement of one of the bromine substituents in the resulting reactive polymer PSBBr2 with tert-butylphenyl groups led to the common intermediate PSBPhBr. A series of organoboron quinolate polymers PSBPhQ were then obtained in high isolated yields (65-85%) by in situ treatment of PSBPhBr with differently substituted 8-hydroxyquinoline derivatives. All the quinolate polymers were fully characterized by multinuclear NMR spectroscopy, elemental analysis, gel permeation chromatography in-line with multiangle laser light scattering (GPC-MALLS), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). Luminescence measurements revealed distinct emission bands, ranging from the blue to the red region (486-615 nm), depending on the substitution pattern on the quinolate ligands.