The synthesis of π-electron molecular rods with a thiophene or thieno[3,2-b]thiophene core unit and sulfur alligator clips

A series of short oligo(p-phenylene-ethynylene)- and oligo(p-phenylenevinylene)-type molecular rods with an electronically rich thiophene or thieno[3,2-b]thiophene core unit and sulfur anchoring groups (AcS−, t-BuS−) at the termini have been synthesised using Sonogashira coupling or Horner–Wadsworth–Emmons (E)-olefination methodology. The collection of linear/bent, conjugated/cross-conjugated systems has been characterised by UV–vis and fluorescence spectroscopy, optical/calculated HOMO–LUMO gaps and calculated excitation energies.