From Saddle-Shaped to Planar Cyclic Oligothienoacenes: Stepped-Cyclization and Their Applications in OFETs

Abstract

A series of cyclic oligothienoacenes (1, 3, and 4) have been successfully synthesized through a stepped-cyclization synthetic strategy from tetra[3,4-thienylene] (2). Single-crystal X-ray diffraction analysis combined with theoretical calculations elucidated that the molecular configuration transforms from the saddle shape of 2 to the quasi-saddle shape (3b, 3c), then to the quasi-helical shape (4b), and at last to the quasi-plane shape (1, 3a, 4a). Organic field-effect transistors (OFETs) based on 1, 3a, and 4a were fabricated. The field-effect mobilities of 7.5 × 10, 2.6 × 10, and 6.8 × 10 cm V s were obtained for 1, 3a, and 4a, respectively. Compounds 3a and 4a can act as air-stable p-type organic semiconductors, while 1 is sensitive to the air.

End‐substituted thiahelicenes for electronic device applications

“…Thus, a comprehensive understanding of electronic structures, as well as spectral properties of these radical cations of thia[n]helicenes, is needed to find applications for these systems as organic electronic devices. Although some scattered experimental studies are available for neutral thia[n]helicenes and their corresponding radical cations of thia[n]helicenes, [ 16–24 ] to the best of our knowledge, no systematic theoretical studies are available for these helicenes. A few attempts have been made to study π‐dimerization of radical cations of linearly conjugated oligothiophenes.…”

Systematic Synthesis of Tetrathia[8]circulenes: The Influence of Peripheral Substituents on the Structures and Properties in Solution and Solid States

“…Replacement of benzene rings in [ n ]­circulenes with heteroles such as furan, pyrrole, and thiophene dramatically alters their electronic properties. Recently, hetero[8]­circulenes are expected to be applicable for the organic electronic materials based on the effective electronic perturbation by heteroatoms. − …”

“…However, the synthesis of disk-shaped molecules annulated by thiophenes are quite limited. ,, Octathia­[8]­circulene and tetra­selenatetrathia­[8]­circulene are a class of thiophene-annulated hetero[8]­circulenes, which exhibit excellent charge transporting properties (Figure ). , However, the lack of peripheral substituents in octathia­[8]­circulene and tetra­selenatetrathia­[8]­circulene cause low solubility in common organic solvents, hampering fine-tuning of photophysical and electrochemical properties and controlling packing structures in the solid state. In 2015, Wong and co-workers have reported the first successful synthesis of tetrathia­[8]­circulene as a new entry of thiophene-fused [8]­circulenes.…”

Recent Advances in Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds

“…CR2017, Section 6.1.5) using β,β-COTh-based starting materials ( Scheme 255 ). 476 The tetrakis(trimethylsilyl)-substituted β,β-COTh derivative 253.1 was quadruply deprotonated by n -BuLi and then reacted with bis(phenylsulfonyl)sulfide to give the doubly annulated product 255.1 in 31% yield. The four TMS groups were quantitatively acidolyzed by TFA, and the resultant compound 255.3 underwent quadruple deprotonation by LDA, followed by double annulation, to yield the “sulflower” 255.6 in 60% yield.…”