Reduction versus Rearrangement of 6,13-Dihydro-6,13-diarylpentacene-6,13-diols Affording 6,13- and 13,13-Substituted Pentacene Derivatives

Pentacene has excellent semi-conducting properties but its practical use in organic thin film transistors (OTFTs) gives rise to a lot of problems caused by its sensitivity to oxygen and its very low solubility. In order to solve the problems involved in the use of pentacene, different aryl substituents were introduced on the 6- and 13-positions. Formation of the pentacene ring system may be accompanied by the rearrangement of the starting dihydropentacenediol to a 13,13ʹ-disubstituted pentacen-6-one for electron-rich aryl substituents. 6-Monosubstituted pentacenes were also prepared.