Related Experiment Video
Updated: Mar 9, 2026
![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
High brightness in bis(tri-isopropylsilyl)ethynyl-functionalized polycyclic aromatic hydrocarbons: localized
Kais Dhbaibi1, Huong Le Thi1,2, Jérôme Marrot1
1UMR CNRS 8180, UVSQ, Institut Lavoisier de Versailles, Université Paris-Saclay 45 Avenue des Etats-Unis 78035 Versailles Cedex France michel.frigoli@uvsq.fr.
Abstract:
Recent studies on acenes have highlighted a localized representation (LR) of aromatic sextets, challenging Clar's classical model of migrating sextets. Here, we extend this framework to peri-fused systems by investigating bis(tri-isopropylsilyl)ethynyl (TIPS)-functionalized polycyclic aromatic hydrocarbons (TIPS-PAHs) namely TIPS-anthanthrene (TIPS-ATT), TIPS-pyranthrene (TIPS-PYR) and TIPS-dibenzo[pyranthrene] (TIPS-DBPYR) as test beds for LR. Crystal structures provide direct evidence for determining the Fries canonical structures, with bond lengths and bond length alternation (BLA) at the zig-zag edge offering robust criteria for positioning aromatic sextets. While NICS and HOMA indices are broadly consistent with these assignments, their interpretation should be considered with some caution. Optical studies reveal progressive bathochromic shifts (491-599 nm) with increasing conjugation, but absorption strength and fluorescence quantum yield depend critically on the mode of π-extension: catacondensation enhances brightness, whereas linear extension diminishes it. Remarkably, TIPS-PYR combines a record molar absorption coefficient (>200 000 M-1 cm-1) with a high fluorescence quantum yield (Φ F = 0.93), yielding a molar brightness comparable to giant nanoribbons. Stability assays show that TIPS-ATT and TIPS-PYR are bench stable, whereas TIPS-DBPYR, despite reduced fluorescence efficiency, exhibits enhanced photostability relative to TIPS-pentacene (TIPS-PEN) and satisfies the energetic criterion for singlet fission. These findings establish LR as a robust framework for describing peri-fused PAHs, identify TIPS-PYR as an exceptionally bright dye, and position TIPS-DBPYR as a promising singlet fission material.
More Related Videos
09:22Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
06:55Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Related Concept Videos
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group...
Aromatic Hydrocarbon Anions: Structural Overview
Due to the absence of continuous...
Five-Membered Heterocyclic Aromatic Compounds: Overview
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
Variables Affecting Phosphorescence and Fluorescence
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene