On-Surface Synthesis of Helicene Oligomers

Chemistry. 2024 Apr 8:e202304127. doi: 10.1002/chem.202304127. Online ahead of print.

Abstract

We report on-surface synthesis of heterochiral 1D heptahelicene oligomers after deposition of a racemic heptahelicene monomer on an Au(111) surface followed by Ullmann coupling under ultrahigh vacuum conditions. Structure, chirality and mode of adsorption of the resulting dimers to octamers are inferred from the scanning probe microscopy and theoretical calculations.

Keywords: Polymerization; Ullmann coupling; chirality; helicene; probe particle model; scanning probe microscopy.