Anthracene-Arrangement-Dependent Emissions of Crystals of 9-Anthrylpyrazole Derivatives

Abstract

We have designed and synthesized a series of 9-anthrylpyrazole derivatives 1,4-bis(3-(9-anthryl)-1-pyrazolylmethyl)benzene (1), 1-(3-(9-anthryl)-1-pyrazolylmethyl)-4-(5-(9-anthryl)-1-pyrazolylmethyl)benzene (2), 1,4-bis(3-(9-anthryl)-1-pyrazolyl)benzene (3), and 1-(3-(9-anthryl)-1-pyrazolyl)-4-(5-(9-anthryl)-1-pyrazolyl)benzene (4). All compounds formed two types of crystals that exhibited anthracene-arrangement-dependent emission colors. For instance, crystal 1a with strong π-overlap between anthracene moieties exhibited an emission maximum at 515 nm, while 1b with no such interchromophore interactions displayed an emission band at 424 nm. The fluorescence quantum yield (ΦF) measurements showed that the blue-emitting crystals have high quantum yields (ΦF = 0.46 for 1b, 0.90 for 2a, 0.91 for 2b, 0.77 for 3b, and 0.51 for 4a), suggesting their potential as blue emitters in optoelectronics.

Aggregation‐Induced Photoluminescent Changes of Naphthyridine–BF2 Complexes

“…Generally, an increased planarity increases the Φ F , and more intermolecular π–π interactions lead to a lower Φ F 20a. 28 The N form of 1 , with fewer head‐to‐tail π–π interactions, is more planar than the B form, and thus the former has a higher Φ F (0.44) than that of the latter (0.20). Furthermore, complex 2 , which has multiple π–π interactions and receives contributions from both face‐to‐face and head‐to‐tail packing, displays the lowest Φ F value (0.10) of all the complexes reported in the present system.…”

Engineering Stacks of V‐Shaped Polyaromatic Compounds with Alkyl Chains for Enhanced Emission in the Solid State

“…In contrast, dimeric stacks of polyaromatic molecules have received considerable attention, because their structures sometimes exhibit intriguing fluorescence behavior derived from the formation of excimers. [8] To exploit anew class of polyaromatic solids with agreater emissive ability,wedesigned aV -shaped polyaromatic compound bearing bulky substituents on the convex side to engineer 1) the dimeric stack of the bent polyaromatic frameworks (Figure 1c)a nd 2) the layered arrays of the polyaromatic dimers through intermolecular interactions between the substituents.H ere we report the unusual emission behavior of V-shaped bisanthracene derivative 1 with three butyl groups (Figure 1d)i nt he solid state. [8] To exploit anew class of polyaromatic solids with agreater emissive ability,wedesigned aV -shaped polyaromatic compound bearing bulky substituents on the convex side to engineer 1) the dimeric stack of the bent polyaromatic frameworks (Figure 1c)a nd 2) the layered arrays of the polyaromatic dimers through intermolecular interactions between the substituents.H ere we report the unusual emission behavior of V-shaped bisanthracene derivative 1 with three butyl groups (Figure 1d)i nt he solid state.…”

Tuning the Solid‐State Optical Properties of Tetracene Derivatives by Modification of the Alkyl Side‐Chains: Crystallochromy and the Highest Fluorescence Quantum Yield in Acenes Larger than Anthracene

“…[20] Another important approach involves tuning the packing and arrangement of molecules in the solid state. [21] Tohnai and co‐workers recently noted the significance of dimensionality, as well as the rigidity, of molecular arrangements in their study on the control of fluorescence in organic salts of anthracene‐2,6‐disulfonic acid with alkyl amines. [22] We also investigated the fluorescence properties of several alkyl‐substituted anthracenes ( 18 – 23 ) and found that some of these derivatives exhibited high quantum yields in the solid state (Table 1).…”