Oligothiophenes. Part 4: Formation and characterization of stable radicals from novel bis- and tris-bithiophene methanes

Two star-shaped structures of the bis- and tris-thiophene methane types have been synthesized in a facile two-step synthesis. The resulting bis- and tris-thiophene methanes readily react with oxygen both as solids and in solution to yield stable radicals. The formed radicals, which were investigated using electron paramagnetic resonance (EPR), were found to be residing on the central carbons of the bis- and tris-thiophene methanes.