Dimethylformamide → 4-(5-Bromo-6-chloro-pyridine-3-sulfonyl)-5-nitro-thiophene-2-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

4-Bromo-5-nitro-thiophene-2-carboxylic acid methyl ester (5.0 g, 19.9 mmol) was dissolved into DMF (20 mL) and cooled to 0° C. To this was added a solution of 5-bromo-6-chloro-pyridine-3-sulphenic acid (Example 118, step a) (1.8 g, 6.6 mmol) in DMF (20 mL) dropwise for 2 hours. The reaction was then warmed to RT and allowed to continue to stir for an additional 2 hours. The reaction was concentrated in vacuo and purified by SiO2 flash column chromatography (Biotage—40 M, 25% EtOAc in hexanes). The product was isolated as a white solid (2.5 g, 48%). ESI-MS (m/z): Calcd. for C11H6BrClN2O6S2: 440.8 (M+H); found: 441.0.

Provenance & Evidence