Cyclobishelicenes: Shape-Persistent Figure-Eight Aromatic Molecules with Promising Chiroptical Properties

Antoine Robert (1) , Guilaume Naulet (1) , Harald Bock (1) , Nicolas Vanthuyne (2) , Marion Jean (2) , Michel Giorgi (3) , Yannick Carissan (2) , Christie Aroulanda (4) , Antoine Scalabre (5, 1) , Emilie Pouget (6) , Fabien Durola (1) , Yoann Coquerel (2)

1 CRPP - Centre de Recherche Paul Pascal
2 ISM2 - Institut des Sciences Moléculaires de Marseille
3 FSCM - Fédération des Sciences Chimiques de Marseille
4 ICMMO - Institut de Chimie Moléculaire et des Matériaux d'Orsay
5 ISM - Institut des Sciences Moléculaires
6 CBMN - Chimie et Biologie des Membranes et des Nanoobjets

Cyclobis[n]helicenes (n = 3 or 5) are chiral D2-sym- metric p-conjugated macrocycles with stable lemniscular, or figure-eight, shapes. The conformational analysis of five dif- ferent cyclobis[n]helicenes revealed that these molecules can only exist as their lemniscular conformers with high barriers to enantiomerization (> 200 kJ/mol). The enantiomers of a cyclobis[5]helicene were resolved by HPLC and their un- usual chiroptical properties were attributed to the inherent chirality of their macrocyclic figure-eight.

Mots clés: aromatic compounds; chirality; chiroptical properties; conformation analysis; helical structures

Domaines: Chimie organique

Antoine Robert, Guilaume Naulet, Harald Bock, Nicolas Vanthuyne, Marion Jean, et al.. Cyclobishelicenes: Shape-Persistent Figure-Eight Aromatic Molecules with Promising Chiroptical Properties. Photography. France. 2019. ⟨hal-02332131⟩