Dimethylformamide → Ethyl 2-bromo-6-formyl-4H-thieno[3,2-b]pyrrole-5-carboxylate

Participants

Reaction Steps

To DMF (2.05 mL) cooled by ice/water was added POCl3 dropwise and the mixture was stirred for 30 min. A solution of carboxylate 61 (1.96 g, 7.15 mmol) in DMF (2.5 mL) was added at this temperature and the mixture was allowed to warm to room temperature then heated to 60° C. After 16 h, the reaction mixture was cooled to room temperature, and poured into ice/water. The mixture was extracted with EtOAc (3×20 mL) and the combined organic layers were washed with aqueous saturated NaHCO3 and brine, dried over Na2SO4. After removed the organic solvent, the residue was purified by column chromatography (EtOAc/Hexane: 1/4) to give the desired aldehyde 62 (1.62 g, 75%) as a white solid.

Provenance & Evidence