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Updated: Nov 30, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Isoacenofuran: a novel quinoidal building block for efficient access to high-ordered polyacene derivatives
Kei Kitamura1, Ryoji Kudo, Haruki Sugiyama
1Department of Applied Chemistry for Environment, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan. thamura@kwansei.ac.jp.
Abstract:
Herein, a simple and practical method for generating isoacenofuran, a new π-extended quinoidal building block, was developed. A three-step protocol involving double nucleophilic additions of alkynyllithiums to acene-2,3-dicarbaldehyde, mono-oxidation, and acid-promoted cyclization enables the generation of the target molecule, which is trapped by a dienophile to produce highly condensed acenequinones. Further transformations by double nucleophilic additions of alkynyllithium to hexacenequinone, followed by reductive aromatization, produce tetraalkynylhexacenes with a remarkably higher stability than that of the previously reported substituted hexacenes.
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