Studies on the stereochemical behaviors of a winding vine-shaped molecular wire of a bithiophene dimer with molecular asymmetry†

Multiple ring-closing metathesis of oligomeric bithiophene smoothly formed a winding vine-shaped oligomer with molecular asymmetry. Stereochemical studies suggested that the dimeric 1 : 1 meso and racemic stereochemical mixture showed the conversion to a meso-enriched product upon standing in the solid state, while the obtained meso compound reverted to the meso and racemic mixture upon heating the solution in chloroform at 50 °C for 30 min. On the other hand, heating of the meso isomer in the solid state at 80 °C for 3 days did not lead to isomerization.