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Updated: Sep 14, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
C2-Symmetric Perylene-Embedded Double [5]Helicenes
Asim Swain1, Frank Rominger1, Michael Mastalerz1
1Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
Abstract:
High quantum yields and dissymmetry factors are key to enhancing the chiroptical properties of [n]helicene-functionalized polycyclic aromatic hydrocarbons for the development of circularly polarized materials. In a two-step synthesis, a C2-symmetric perylene-embedded double [5]helicene was obtained through Suzuki-Miyaura cross-coupling and base-catalyzed condensation. With a configurational stability of 23 kcal mol-1, the short-lived enantiomers were separated using chiral HPLC. Compared to pristine [5]helicene, the compound shows enhanced (chir)optical properties with a quantum yield of 0.7, a gabs of up to 8.8 × 10-3, and a glum of 0.7 × 10-3.
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