title: Fused Helicene Chains: Towards Twisted Graphene Nanoribbons.
abstract: By taking advantage of an unexpected regioselectivity of intramolecular Scholl reactions on pentaphenylene compounds that favors distorted [5]helicenes over their flat counterparts, a new synthetic approach to twisted graphene nanoribbons has been designed based on side-fused di-tert-butyl-[5]helicene fragments. Syntheses of both small monomers and dimers have been achieved and their structures have been studied. An iterative synthetic strategy has been developed for the formation of longer flexible precursors, which relies on the step-by-step elongation of mono-functionalized oligomeric chains. The flexible trimer and tetramer have, thus, been synthesized and submitted to intramolecular Scholl reactions, which revealed important purification and characterization issues.
authors.affiliation: Centre de Recherche Paul Pascal, CNRS & Université de Bordeaux, 115 Avenue Schweitzer, 33600, Pessac, France.
authors.forename: Anirban
authors.initials: A
authors.lastname: Pradhan
authors.affiliation: Centre de Recherche Paul Pascal, CNRS & Université de Bordeaux, 115 Avenue Schweitzer, 33600, Pessac, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Dechambenoit
authors.affiliation: Centre de Recherche Paul Pascal, CNRS & Université de Bordeaux, 115 Avenue Schweitzer, 33600, Pessac, France.
authors.forename: Harald
authors.initials: H
authors.lastname: Bock
authors.affiliation: Centre de Recherche Paul Pascal, CNRS & Université de Bordeaux, 115 Avenue Schweitzer, 33600, Pessac, France.
authors.forename: Fabien
authors.identifier: http://orcid.org/0000-0002-9720-4848
authors.initials: F
authors.lastname: Durola
keywords: Scholl reaction; curved aromatic compounds; graphene; helical structures; polycycles