Dimethylformamide → 5,6-Difluoro-1h-indole-3-carbaldehyde

Participants

Reaction Steps

To an ice-cooled solution of oxalyl chloride (1.21 mL, 13.8 mmol) in CH2Cl2 (40 mL) was added a solution of DMF (2.02 mL) in CH2Cl2 (40.0 mL). The reaction was stirred for 30 min, then 5,6-difluoro-1H-indole [169674-01-5] (2.00 g, 13.1 mmol) was added in one portion. The reaction mixture was allowed to warm to RT overnight. Volatiles were evaporated, and the residue was taken up in THF (20 mL) and 20% aqueous ammonium acetate solution (20 mL). The resulting mixture was heated to reflux for 30 min. After cooling, the mixture was treated with saturated aqueous NaHCO3 solution and extracted three times with EtOAc. The combined organic layers were dried (phase separator) and evaporated in vacuo to afford the title compound as a beige solid: MS (LC/MS): 182.0 [M+H]+; tR (HPLC conditions c): 3.94 min. The material thus obtained was used in the next step without further purification.

Provenance & Evidence