Uses
5-Bromothiophene-3-carboxylic acid serves as a precursor for esterification to the tertiary ester, and as the starting material for a three-step synthesis of the bithiophene monomer bis(2-octyldodecyl)-5,5′-dibromo-[2,2′-bithiophene]-4,4′-dicarboxylate[6-7].
Synthesis
(d) Synthesis of 5-bromo-3-thiophenecarboxylic acid: a glacial acetic acid solution of bromine was prepared by dissolving 16 g of Br2 (0.1 mol) in 200 ml of glacial acetic acid. This solution was slowly added dropwise to 100 ml of glacial acetic acid solution containing 3-thiophenecarboxylic acid (12.8 g; 0.1 mol). The reaction mixture was stirred at room temperature for 20 minutes. Upon completion of the reaction, the mixture was poured into a vessel containing water and ice to quench the reaction and promote precipitation of the product. The resulting white precipitate was collected by filtration and washed with water to remove residual glacial acetic acid. Finally, the product was purified by recrystallization from water to give 5-bromo-3-thiophenecarboxylic acid in 70% yield.
References
[1] Tetrahedron Letters, 2013, vol. 54, # 11, p. 1460 - 1462
[2] Patent: US4767758, 1988, A
[3] Journal of Materials Chemistry C, 2018, vol. 6, # 14, p. 3731 - 3742
[4] Chemistry of Materials, 2010, vol. 22, # 19, p. 5617 - 5624
[5] Angewandte Chemie - International Edition, 2018, vol. 57, # 26, p. 7714 - 7718
[6]
Helgesen, M., Bjerring, M., Nielsen, N. C., Krebs, F. C. (2010). Influence of the Annealing Temperature on the Photovoltaic Performance and Film Morphology Applying Novel Thermocleavable Materials. Chemistry of Materials, 22(19), 5617–5624.
https://doi.org/10.1021/cm1019537 [7]
Kini, G. P., Lee, E. J., Jeon, S. J., Moon, D. K. (2021). Understanding the Critical Role of Sequential Fluorination of Phenylene Units on the Properties of Dicarboxylate Bithiophene‐Based Wide‐Bandgap Polymer Donors for Non‐Fullerene Organic Solar Cells. Macromolecular Rapid Communications, 42(9).
https://doi.org/10.1002/marc.202000743
