Related Experiment Video
Updated: Dec 20, 2025

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
NIR-Absorbing π-Extended Azulene: Non-Alternant Isomer of Terrylene Bisimide
Bartłomiej Pigulski1, Kazutaka Shoyama1, Frank Würthner1,2
1Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Abstract:
The first planar π-extended azulene that retains aromaticity of odd-membered rings was synthesized by [3+3] peri-annulation of two naphthalene imides at both long-edge sides of azulene. Using bromination and subsequent nucleophilic substitution by methoxide and morpholine, selective functionalization of the π-extended azulene was achieved. Whilst these new azulenes can be regarded as isomers of terrylene bisimide they exhibit entirely different properties, which include very narrow optical and electrochemical gaps. DFT, TD-DFT, as well as nucleus-independent chemical shift calculations were applied to explain the structural and functional properties of these new π scaffolds. Furthermore, X-ray crystallography confirmed the planarity of the reported π-scaffolds and aromaticity of their azulene moiety.
More Related Videos
Related Concept Videos
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group...
Isomerism in Alkenes
An isomer is called cis-2-butene when the methyl groups are on the same side of the double bond, and the other stereoisomer, in which methyl groups are on the opposite side of the double bond, is called trans-2-butene. The cis and trans stereoisomers are not...
Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism
Disubstituted Cyclohexanes: cis-trans Isomerism
In cyclohexane, the substituents can occupy different positions generating distinct isomers....
Aromatic Hydrocarbon Anions: Structural Overview
Due to the absence of continuous...
π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds

