Work

Synthesis of Thieno[3,2-b]thiophenes from 2,5-Dicarbonyl 3-Nitrothiophenes via Nucleophilic Aromatic Substitution of the Nitro Group with Thiolates

Year: 2024

Type: article

Abstract: In this study, we developed an efficient strategy for constructing thieno[3,2-b]thiophene molecules from 3-nitrothiophenes, containing carbonyl fragments at the C-2 and C-5 atoms, by nucleophilic aromatic substitution of the nitro group in these substrates. It was shown that the reaction of 3-nitrothiophene-2,5-dicarboxylates with thiophenols, thioglycolates and 2-mercaptoacetone in the presence of K2CO3 proceeds rapidly via nucleophilic displacement of the nitro group with the formation of 3-sulfenylthiophene-2,5-dicarboxylates. Further treatment of the resulting thiophene-2,5-dicarboxylates, which have -SCH2CO2Alk or -SCH2COMe moiety at C-3 atom, with sodium alcoholates afford obtaining 2,3,5-trisubstituted thieno[3,2-b]thiophene derivatives according to the Dieckman condensation. In turn, the reaction of methyl 5-formyl-4-nitrothiophene-2-carboxylate with methyl thioglycolate or 2-mercaptoacetone in the presence of K2CO3 proceeds to directly form 2,5-disubstituted thieno[3,2-b]thiophenes.

Source: Organics

DOI: 10.3390/org5040027

Authors: Roman A. Irgashev, Nikita A. Kazin

Institutions: Russian Academy of Sciences, Institute of Organic Synthesis

Language: English

Topic: Synthesis of heterocyclic compounds

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,137

Funder: Russian Science Foundation