Synthesis of aryl-substituted thieno[3,2-b]thiophene derivatives and their use for N,S-heterotetracene construction

Abstract

Fiesselmann thiophene synthesis was applied for the convenient construction of thieno[3,2-b]thiophene derivatives. Thus, new 5- or 6-aryl-3-hydroxythieno[3,2-b]thiophene-2-carboxylates were obtained by condensation of 5- or 4-aryl-3-chlorothiophene-2-carboxylates, respectively, with methyl thioglycolate in the presence of potassium tert-butoxide. The saponification of the resulting esters, with decarboxylation of the intermediating acids, gave the corresponding thieno[3,2-b]thiophen-3(2H)-ones. The latter ketones were used to synthesize new N,S-heterotetracenes, namely 9H-thieno[2',3':4,5]thieno[3,2-b]indoles by their treatment with arylhydrazines in accordance with the Fischer indolization reaction.

A general approach to construct selenopheno[3,2-b]indole-cored molecules using Fischer indolization

“…Previously, in a series of our works, we have suggested a convenient strategy for the construction of various thieno[3,2- b ]indoles and thieno[3,2- b ]indole-fused molecules based on the Fischer indole synthesis. 25 In the context of this strategy, the thieno[3,2- b ]indole fragment of the desired molecule was constructed by Fischer indolization of the thiophen-3(2 H )-one arylhydrazone part in intermediate C , formed in situ by the reaction of thiophen-3(2 H )-ones A 26–29 or 3-aminothiophenes B 30–34 with arylhydrazines. In turn, substrates A and B were generated respectively from 3-hydroxy- or 3-aminothiophene-2-carboxylates.…”

An Approach to the Construction of Benzofuran-thieno[3,2-b]indole-Cored N,O,S-Heteroacenes Using Fischer Indolization

“…Indeed, we have previously suggested two similar approaches both based on the Fischer indolization reaction for the synthesis of TI derivatives and TI-cored heteroarenes, including BTTI and BSTI compounds. According to the first way, we have prepared TI compounds by the reaction of thiophen-3­(2 H )-ones HT-2 with arylhydrazines in glacial acetic acid, initially to form arylhydrazones AHT , that directly afforded the target products via Fischer indolization. − The key substrates HT-2 were readily obtained from the corresponding 3-hydroxythiophene-2-carboxylates HT-1 by their cleavage under acidic or basic reaction conditions (route A, Scheme ). We have also elaborated the second way toward TI compounds from 3-aminothiophene-2-carboxylates AT-1 as the starting substrates using a one-pot synthetic procedure. − In this case, 3-aminothiophenes AT-2 were in situ generated from esters AT-1 by their saponification with alkali and further treatment of the obtained salts with glacial acetic acid.…”

Influence of Molecular Symmetry and Terminal Substituents on the Morphology and OFET Characteristics of S,N-Heteropentacenes

“…Within the past few years, the development of OFETs has been witnessed by efforts to reveal the charge transportation mechanism despite being under debate, rational molecular design, and optimized device fabrication, such as monolayer OFET devices, with assistance of experiments and theoretical calculation. Above the length scale of a molecule, solid-state morphology acts as an important intermedium to transfer molecular properties into useful device performances .…”

“…On the other hand, pyrrole-containing indolo­[3,2- b ]­carbazole (ICZ) derivatives deliver a mobility of 1 cm 2 V –1 s –1 . Although the synthetic chemistry of heteroacene has been vigorously developed, ,− the key factors that affect the assembly behaviors and thin-film morphology of heteroacenes are only sparsely discussed.…”