Heterocyclic heptamers containing thiophene and pyrrole units: Synthesis and properties

Studies on septithiophenes are relatively rare compared to the available detailed investigations of sexithiophenes. The balance is redressed here by a report of the synthesis, electrochemistry and spectroscopic properties of a new α,ω‐disubstituted septithiophene and two pyrrole‐containing septithiophene and two pyrrole‐containing septithiophene analogues. Two different routes are described by which it was attempted to impart solubility in organic solvents to septithiophenes–one unsuccessful and one successful. Evidence of an unusual three‐electron transfer process is also presented.