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Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
Published on: April 1, 2013
Synthesis, properties, crystal structures, and semiconductor characteristics of naphtho[1,2-b:5,6-b']dithiophene and
Shoji Shinamura1, Eigo Miyazaki, Kazuo Takimiya
1Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan.
Abstract:
In this paper we present the synthesis, structures, characterization, and applications to field-effect transistors (FETs) of naphtho[1,2-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 [1]benzothieno[2,3-b][1]benzothiophene (BTBT) and [1]benzoselenopheneno[2,3-b][1]benzoselenophene (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.
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