Thiophene-backbone arcuate graphene nanoribbons: shotgun synthesis and length dependent properties†

Abstract

Efficient synthetic methods are urgently needed to produce graphene nanoribbons (GNRs) with diverse structures and functions. Precise control over the topological edges of GNRs is also crucial for achieving diverse molecular topologies and desirable electro-optical properties. This study demonstrates a highly efficient “shotgun” synthesis of thiophene-backbone arcuate GNRs, offering a significant advantage over tedious iterative synthesis. This method utilizes a one-pot, three component Suzuki–Miyaura coupling for the precursor, followed by a Scholl reaction for cyclization. The resulting arcuate GNRs have sulfur atoms embedded in the carbon backbone with a combined armchair, cove, and fjord edge structure. This multi-edge architecture is further modified by high-yield oxidation of the electron-rich sulfur atoms to electron-deficient sulfones, enabling precise regulation of the GNRs' electronic properties. These arcuate GNRs with diverse edge structures, heteroatom doping and precise lengths open exciting avenues for their application in optoelectronic devices.