360576-01-8

6-Bromobenzo[b]thiophene-2-carboxylic acid methyl ester is used in the synthesis of benzothiophene derivatives as histone deacetylase inhibitors.

GENERAL METHOD: Compound 1a or 1b (9.90 mmol) was dissolved in DMF (20 mL) under stirring conditions, followed by the sequential addition of methyl mercaptoacetate (10.9 mmol) and potassium carbonate (39.6 mmol). The reaction mixture was stirred continuously at 60 °C for 15 hours. After completion of the reaction, the DMF solvent was removed by distillation under reduced pressure. Water (50 mL) was added to the residue, which was then extracted with ethyl acetate (2 x 40 mL). The organic phases were combined, dried with anhydrous sodium sulfate, filtered, and the solvent was removed by reduced pressure distillation to give the final target product, methyl 6-bromobenzo[b]thiophene-2-carboxylate (2a or 2b).

[1] European Journal of Medicinal Chemistry, 2017, vol. 125, p. 538 - 550
[2] Patent: WO2012/149413, 2012, A1. Location in patent: Page/Page column 58
[3] Journal of Medicinal Chemistry, 2016, vol. 59, # 1, p. 264 - 281
[4] Journal of Medicinal Chemistry, 2015, vol. 58, # 18, p. 7241 - 7257
[5] Patent: JP2015/89879, 2015, A. Location in patent: Paragraph 0016; 0047; 0048