From 1,4-Phenylenebis(phenylmaleate) to a Room-Temperature Liquid-Crystalline Benzo[ghi]perylene Diimide
Résumé
The photocyclization of tetraethyl 1,4‐phenylenebis(phenylmaleate) in the presence of iodine and oxygen predominantly yields tetraethyl [5]helicene‐5,6,9,10‐tetracarboxylate, together with small amounts of tetraethyl dibenz[a,h]anthracene‐5,6,12,13‐tetracarboxylate and tetraethyl benzo[ghi]perylene‐3,4,11,12‐tetracarboxylate. The helicene tetraester is planarized to the benzoperylene tetraester by Scholl reaction with AlCl3 followed by reesterification of the partially hydrolyzed crude product. Subsequent treatment with a branched alkylamine yields a columnar liquid‐crystalline benzoperylene diimide whose mesophase is stable at room temperature despite its limited and non‐centrosymmetric alkyl periphery. Its absorption spectrum is markedly red‐shifted compared to that of a similar benzoperylene triimide.
Domaines
Chimie organique| Origine | Fichiers produits par l'(les) auteur(s) |
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