π‐Conjugated 2,2′:6′,2″‐Bis(terpyridines): Systematical Tuning of the Optical Properties by Variation of the Linkage between the Terpyridines and the π‐Conjugated System

Abstract

Abstract2,2′:6′,2″‐Terpyridines bearing well‐defined π‐conjugated substituents at the 4′‐position are known to exhibit interesting electronic and optical properties. The systematic variation of both the spacer unit and the linker in conjugated bis(terpyridines) has resulted in a library of π‐conjugated systems, enabling the study of the structure–property relationships of these materials. We have proven the Huisgen 1,3‐dipolar cycloaddition reaction to be a versatile tool for connecting conjugated systems, even though the conjugation is hindered by the introduced triazole moiety. All the terpyridine derivatives were fully characterized by 1H and 13C NMR spectroscopy, UV/Vis absorption and emission measurements as well as MALDI‐TOF MS. Thin films of the materials were produced by spin‐coating and subsequently characterized. Because tuning of the band gap of the materials over a wide range is possible, quantum yields of up to 85 % and extinction coefficients of around 100000 M–1 cm–1 could be observed, the compounds might be promising candidates for the design of new functional supramolecular materials.

Postfunctionalization of Luminescent Bipyridine PtII Bisacetylides by Click Chemistry

“…2b), which enhance the electron-donating character of the coordinated phenylacetylides, thus, raising the HOMO. [25] Steric effects that induce a twist of the triazole ring and weaken the mesomeric interactions through the nitrogen atoms involved are considered to be responsible for the poorly mediated conjugation. As expected, no remarkable difference was observed between 5-substituted complexes bearing TMS-protected or unprotected ethynyl groups at the bpy ligand (cf.…”

π‐Conjugated Donor and Donor–Acceptor Metallo‐Polymers

“…Compounds 1 and 2 were prepared following previously published protocols. [30,31] Details on the synthesis of the polymers, the instrumentation and device preparation are given in the Supporting Information.…”

Highly Luminescent 4′‐(4‐ethynylphenyl)‐2,2’:6’,2’’‐Terpyridine Derivatives as Materials for Potential Applications in Organic Light Emitting Diodes

“…It is worth noting that the obtained values of quantum yield are much higher than those measured for previously studied terpyridine derivatives (Φ= 0.08‐0.62) . The high quantum yield of T1 ‐ T4 can be attributed to almost coplanar geometry and extension of the π‐conjugated system via the presence of ethynyl fragment in the molecules . All obtained results suggest that novel terpyridine derivatives T1 ‐ T4 can have highly efficient electroluminescent properties in OLED devices.…”