Syntheses and Characterization of Luminescent Polymers Containing Rhenium(I) Pyridinyl‐Carbonyl Complexes

Abstract

The syntheses of methacrylate‐ and styrene‐based monomers containing substituted pyridine ligands are reported. The preparation of the corresponding homopolymers has been performed by free radical polymerization by using 2,2′‐azoisobutyronitrile (AIBN) at 60 °C. The high molecular weights, up to 119 000 g · mol−1, and low glass transition (Tg) values (< −43 °C) have been obtained by the copolymerization reaction with butyl acrylate. The free metal homopolymer and copolymer were subsequently metalated by reaction with Re[phen(CO)3(acetone)]+. All polymer materials have been characterized by conventional experimental techniques, such as gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). UV‐Vis and fluorescence spectroscopy have been used to investigate the optical and photophysical properties of the polymers in solid‐state films and in solution. 1H NMR spectra confirmed the structure of the synthesized polymers and contributed to the estimate of the monomer sequences in the copolymer chains. Time‐resolved and emission‐quenching experiments in diluted solutions and on the solid films suggest application of the polymeric materials as oxygen sensors. The morphological aspects of some polymers containing a low amount of rhenium metal complexes have been investigated by scanning electron microscopy (SEM).

Spectroscopic Studies of Phosphazene Polymers Containing Photoluminescent Metal Complexes

“…The spectra of the rhenium compound [L 5 Re(CO) 3 Cl] are different to those of the platinum and palladium compounds due to two-coordinate binding of Re to L 5 compared with three-coordinate binding of L 5 , L 4 or L 1 to the other metals. The resonance Raman spectra generated with 350.7 nm excitation shows a number of bands similar to [Re(bpy)(CO) 3 Cl], but in addition new or significantly shifted features are observed at 1358, 1544 and 1609 cm -1 .…”

“…Sect.). During the preparation of L 2 we observed the appearance of a singlet at δ = 22.70 ppm corresponding to the monosubstituted species L 4 . This phosphazene can be prepared from the reaction between 1 equiv.…”

“…[29] Similarly, the new phosphazenes L 2 , L 3 and L 4 were prepared by the reaction of 1 or 2 equiv. of the sodium salt of HOPhbpyPh with N 3 P 3 (biph) 2 Cl 2 or N 3 P 3 (tBubiph) 2 Cl 2 in the presence of the catalyst, tetrabutylammonium bromide (Scheme 1).…”

“…The synthesis of new polymers containing transitionmetal complexes is an area of research that is attracting increasing interest [1][2][3] due to a diverse range of prospective applications for polymer-based metal complexes, including sensors, [4][5][6][7] biomedical applications [8][9][10] and catalysis. [11,12] Owing to their well-understood emissive properties, [13] metal complexes have attracted attention in the field of organic light-emitting diode (OLED) device construction [14] and examples of electroluminescent polymers containing metal ions as chromophores are also becoming more widespread.…”

Red‐Emitting Polymer Microspheres Containing Zinc Porphyrins

“…[1][2][3][4][5][6][7] To realize full-color display, light-emitting materials with three primary colors, i.e., blue, green, and red, are necessary. Many organic dyes are utilized as emitters of light-emitting materials, but there are relatively few suitable red fluorescent dyes.…”