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Updated: Jun 25, 2025
Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Resolution of 9,10-Diketo[7]helicene and Its Use in One-Step Preparation of Helicene-Based D-A-D Push-Pull Systems
Martin Kos1, Tomáš Beránek1, Ivana Císařová2
1Research Group of Advanced Materials and Organic Synthesis, Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, v. v. i., Rozvojová 135, 165 00 Prague 6, Czech Republic.
Abstract:
Racemic 9,10-diketo[7]helicene was successfully separated into enantiomers using a reversible and stereoselective reaction with 2,2'-diamino-1,1'-binaphthalene with moderate yields but with remarkable purity (>99% de). The enantiomerically pure diketone was used as a convenient starting material for the preparation of helicene-based push-pull molecules, which incorporated aza-aryl acceptors and diarylaminophenylene donor groups in a single step. A series of six push-pull systems, along with three reference molecules without donors, were prepared and studied using UV/vis and fluorescence measurements, circular dichroism, and DFT calculations.
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