o-Carborane functionalized pentacenes: synthesis, molecular packing and ambipolar organic thin-film transistors

Abstract

New 6,13-bis[1′-(CC)-2′-R-1′,2′-C₂B₁₀H₁₀]pentacenes (R = H, Me, Et, n-Bu) are synthesized and fully characterized. The results show that the alkyl substituents on the second cage carbon have a significant impact on the molecular packing, and the incorporation of the o-carboranyl moiety into a π conjugated system can lower both LUMO and HOMO energy levels, converting a typical p-type semiconductor into an ambipolar one.