On‐Surface Interchain Coupling and Skeletal Rearrangement of Indenofluorene Polymers

Abstract

On‐surface synthesis serves as a powerful approach to construct π‐conjugated carbon nanostructures that are not accessible by conventional wet chemistry. Nevertheless, this method has been limited by the types and numbers of available on‐surface transformations. While the majority of successful cases exploit thermally triggered dehalogenative carbon‐carbon coupling and cyclodehydrogenation, rearrangement of appropriate functional moieties has received limited research attention. Here, we describe the unprecedented interchain coupling and thermally induced skeleton rearrangement of (dihydro)indeno[2,1‐b]fluorene (IF) polymers on an Au(111) surface under ultrahigh vacuum conditions, leading to different ladder polymers as well as fully fused graphene nanoribbon segments containing pentagonal and heptagonal rings. Au‐coordinated nanoribbons were also observed. All structures were unambiguously characterized by high‐resolution scanning probe microscopy. The current results provide an avenue to fabricating a wider variety of π‐conjugated polymers and carbon nanostructures comprising non‐hexagonal rings as well as rarely explored organometallic nanoribbons.This article is protected by copyright. All rights reserved