Banana‐Shaped Oligo(aryleneethynylene)s: Synthesis and Light‐Emitting Characteristics

Abstract

Pick of the bunch: Banana‐shaped molecules 1 and 2 containing dimethoxybenzene and pyridine units are highly efficient emitters of violet light despite the interruption of the π conjugation because of meta substitution. The contrasting solvent dependencies of the fluorescence quantum yield values of 1 and 2 are explained by the disparity between the difference density distributions in the excited states of the molecules.

Interplay between H‐Bonding and Preorganization in the Evolution of Self‐Assembled Systems

“…Oligomeric p-systems [4] are promising building blocks to bridge this knowledge gap due to their variable torsional flexibility,w hich in turn allows versatile molecular reorganization upon aggregation. In this context, oligo(p-phenyleneethynylene)s (OPEs) represent ap articularly relevant class of molecules with excellent optical and electronic properties,w hich have been extensively applied in the fields of optoelectronics, [5] sensors, [6] and stimuli-responsive materials. [7] OPEs have also been exploited to create hierarchical self-assembled structures driven by p-stacking and H-bond-ing.…”

Synthesis and optoelectronic properties of 2,6-bis(2-anilinoethynyl)pyridine scaffolds

“…The inherent properties of such ethynylpyridines (conjugation, absorption/emission, pH-dependent speciation, metal binding capability, rigidity, etc. ), 25–27 have been exploited for applications such as liquid crystals, 28 lightemitting materials, 29 rotaxane-type structures, 30 molecular magnets, 31 antiangiogenic activity, 32 polymer composites 33 and coordination complexes. 24,34,35 In contrast, the supramolecular chemistry of 2,6-bis(arylethynyl)pyridines has received little attention, perhaps in part due to the scarcity of uniting the fields of molecule/ion recognition with the synthesis of highly-conjugated, carbon-rich materials.…”

Donor‐substituted distyrylpyrazines: influence of steric congestion on UV–Vis absorption and fluorescence

“…In this context, amino groups as efficient donors are often combined with strong acceptors like nitriles . In addition to electron withdrawing groups on the π‐system, replacing benzene rings with electron deficient heterocycles like pyridine is a successful route to increase the electron affinity. The interaction of these compounds with the environment can result in significant spectroscopic changes, useful for sensing purposes .…”