Synthesis, Properties, Crystal Structures, and Semiconductor Characteristics of Naphtho1,2-b:5,6-b′dithiophene and -diselenophene Derivatives

In this paper we present the synthesis, structures, characterization, and applications to field-effect transistors (FETs) of naphtho1,2-b:5,6-b'dithiophene (NDT) and -diselenophene (NDS) derivatives. Treatment of 1,5-dichloro-2,6-diethynylnaphthalenes, easily derived from commercially available 2,6-dihydroxynaphthalene, with sodium chalcogenide afforded a straightforward access to NDTs and NDSs including the parent and dioctyl and diphenyl derivatives. Physicochemical evaluations of NDT and NDS derivatives showed that these heteroarenes have a similar electronic structure with isomeric 1benzothieno2,3-b1benzothiophene (BTBT) and 1benzoselenopheneno2,3-b1benzoselenophene (BSBS) derivatives, respectively. Although attempts to fabricate solution-processed field-effect transistors (FETs) with soluble dioctyl-NDT (C(8)-NDT) and -NDS (C(8)-NDS) failed, diphenyl derivatives (DPh-NDT and DPh-NDS) afforded vapor-processed FETs showing field-effect mobility as high as 0.7 cm(2) V(-1) s(-1). These results indicated that NDT and NDS are new potential heteroarene core structures for organic semiconducting materials.