Highly Polarized Benzo[k]fluoranthene Imide Derivatives: Large Solvatofluorochromism, Dual Fluorescence and Aggregation Induced Emission Associated with Excited‐State Intramolecular Charge Transfer

Abstract

The highly conjugated imides, 9‐diphenyl‐aminobenzo[k]fluoranthene imide and N‐phenylcarbazo[2,3‐k]fluoranthene imide, were produced by Buchwald‐Hartwig reaction of N‐octyl‐9,10‐dibromobenzo[k]fluoranthene imide with diphenylamine. In a similar manner, reaction of the N‐ethylhexyl‐9,10‐dibromo derivative with carbazole leads to formation of 9‐(N‐carbazoyl)benzo[k]fluoranthene imide. All the benzo[k]fluoranthene imide (BFI) derivatives in solution show remarkable solvatofluorochromism. Diphenylamino and 9‐(N‐carbazoyl) derivatives, having twisted structures, exhibit fluorescence bands at short wavelengths in highly polar solvents, and they emit dual fluorescence in acetone. Moreover, the 9‐(N‐carbazoyl) derivative displays aggregation‐induced emission in highly aqueous acetone solutions. The results of density functional theory calculations demonstrate that a considerable spatial separation exists between the HOMO and LUMO coefficients of the N‐arylamine substituted BFIs. The results indicate that the ground‐to‐excited state transitions of these compounds have intramolecular charge transfer character.

An asymmetric 2,3-fluoranthene imide building block for regioregular semiconductors with aggregation-induced emission properties

“…This could be due to the restriction of intramolecular rotation between the D and A units due to the formation of aggregates. [51][52][53][54] Note that adding more water further causes a decrease in emission due to sedimentation (Fig. S11 †).…”

A Star‐Shaped Solvatofluorochromic Pyrene‐Triarylamine Derivative as a Fluorescent Thermometer over a Wide Temperature Range†

“…The Δ μ value is typically in the range of 3—20 D for known organic ICT compounds [ 16 ] and only rare examples can exceed 30. [ 17 ] The large Δ μ of compound 1 is caused by the strong solvent effect and the relatively large size of the molecule.…”

“…The influence of the solvent orientation polarizability Δ f on the Stokes shift obeys a rough linear relationship with a slope of 1.88 × 10 4 cm –1 . According to the Lippert‐Mataga analysis, [ 16,17 ] the dipole moment difference Δ μ between the ground ( μ g ) and excited states ( μ e ) was estimated to be 38.2 D (see details in SI). The Δ μ value is typically in the range of 3—20 D for known organic ICT compounds [ 16 ] and only rare examples can exceed 30.…”

Isolation and characterisation of a stable 2-azaphenalenyl azomethine ylide

“…This observation demonstrates that the corresponding azomethine ylide 7a is generated as a reactive intermediate by Et 3 N induced deprotonation of 8a. Additionally, reaction of 7a with the as a versatile synthetic intermediate [16][17][18][19] N-(2-ethylhexyl) acenphthylene-5,6-dicarboxylimide 11 was examined. Under similar conditions, this reaction produces the corresponding cycloadduct 12 in 31% yield ( Fig.…”

“…NMR spectra of 7b and 12 were recorded using JEOL-AL400 (400 MHz for 1 H, and 100 MHz for 13 C) and Bruker AVANCE III spectrometers (600 MHz for 1 H, and 150 MHz for 13 C) with TMS as an internal standard. 19 F and 11 B NMR spectra of 8a and 8b were recorded using a JEOL-AL400 spectrometer (126.9 MHz for 11 B, and 372.4 MHz for 19 F) with BF 3 Et 2 O as an external standard. UV-vis and fluorescence spectra of 8a and 8b in DCM were recorded using a JASCO V650 and a SHIMADZU RF-5300PC spectrophotometer, respectively.…”