Syntheses, Structures, and Properties of 2,3,6,7-Tetrathiabenzo[1,3-cd:4,6-c′d′]dipentalene and Its Methyl, Ethyl, Methylthio, and Ethylthio Derivatives: Novel Fused Polynuclear Heteroarenes

Abstract

The title heteroarene (TBD) isoelectronic with perylene was synthesized by way of a dimerization of thieno[2,3-b]thiophene. In addition, 1,4,5,8-tetramethyl, tetraethyl, tetrakis (methylthio), and tetrakis (ethylthio) derivatives were readily obtained from TBD. An X-ray crystallographic analysis of TBD demonstrated that the molecular structure is quite planar and symmetrical, but strained in the bond angles. The crystal structure comprises herringbone-type column stacking with intercolumnar heteroatomic interactions. TBD showed the same oxidation potential as did perylene, and like perylene, formed an iodine complex with a relatively high electrical conductivity of 0.11 S cm−1. On the other hand, all of the TBD derivatives gave poorly conductive iodine complexes. In addition, TBD and the derivatives formed charge-transfer complexes with strong electron acceptors, such as 7,7,8,8-tetracyanoquinodimethane (TCNQ), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (TCNQF4), 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), and 1,1,2,3,4,4-hexacyano-1,3-butadiene (HCBD). These π-complexes, however, were mostly of low conductivity. The electrolyses of TBP gave powdery conductive polymers, whereas those of tetrakis (methylthio) TBD gave crystalline radical cation salts with conductivities of the order of 10−3 S cm−1.

Semiconducting Thienothiophene Copolymers: Design, Synthesis, Morphology, and Performance in Thin‐Film Organic Transistors

“…[80][81][82] For example, Otsubu and co-workers reported an elegant synthesis by the lithiation of 1-trimethylsilylpentadiyne with n-BuLi/t-BuOK, followed by trapping of the resultant anion with carbon disulfide. [81] Ring closure upon work-up afforded 2-trimethylsilylthieno [2,3-b]thiophene, which could readily be desilylated by treatment with tetrabutylammonium fluoride to afford thieno [2,3-b]thiophene. [82] For larger scale preparations, a more convenient route was developed from commercially available 2-thiophenethiol (Scheme 1).…”

Synthesis and properties of mono- and dimetal Fischer multicarbene complexes derived from thiophene and thieno[2,3-b]thiophene

“…11 The C-C bond common to both the chelate and the thiophene rings, have similar distances for 7, 13 and 15 (Table 2).…”

“…However, the synthesis of 4,4′-dibromothieno[2,3-b]thiophene requires the initial formation of 4,4′,5,5′-tetrabromothieno[2,3-b]thiophene, followed by the debromination of the 5-and 5′-positions. 11,15 Thus, as the thiophene results indicated that it was possible to obtain both mono-and bischelated carbene complexes from the tetrabromothiophene precursor, 4,4′,5,5′-tetrabromothieno [2,3-b]thiophene was chosen as substrate to target the formation of both classes of chelated complexes (10, 11, 14 and 15). The reaction of 4,4′,5,5′-tetrabromothieno[2,3-b]thiophene with 2.4 equivalents of n-BuLi, 2 equivalents of metal carbonyl and another addition of 2.4 equivalents n-BuLi, afforded a number of carbene complexes.…”

“…Thieno [2,3-b]thiophene can be prepared from trimethylsilyl-1,3-pentadiyne, 11 while procedures from literature were employed for the preparation of 4,4′,5,5′-tetrabromothieno[2,3-b]thiophene 21 and triethyloxonium tetrafluoroborate. 22 All operations were carried out using standard Schlenk techniques under an inert atmosphere of nitrogen or argon.…”

ChemInform Abstract: The Diyne Reaction of 3,3′‐Bis(phenylethynyl)‐2,2′‐bithiophene Derivatives via Rhodium Complexes: A Novel Approach to Condensed Benzo( 2,1‐b:3,4‐b′)dithiophenes.

“…-The development of new strategies for the syntheses of polycondensed thiophenes has recently received much attention because of the unusual aromatic [I] and photophysical [2] properties displayed by these compounds as well as the potential for use of these derivatives as organic conductors and superconductors [3], electron acceptors [4] and donors [5], photosensitive receptors [6], and as materials for nonlinear optics [7]. -The development of new strategies for the syntheses of polycondensed thiophenes has recently received much attention because of the unusual aromatic [I] and photophysical [2] properties displayed by these compounds as well as the potential for use of these derivatives as organic conductors and superconductors [3], electron acceptors [4] and donors [5], photosensitive receptors [6], and as materials for nonlinear optics [7].…”