4-Toluenesulfonyl chloride → 1-Tosyl-1H-indole-4-carbaldehyde

Participants

Reaction Steps

To a solution of 1H-indole-4-carbaldehyde (2.9 g, 20 mmol) in THF (50 mL) cooled in an ice bath was added NaH (0.96 g, 60% in oil, 24 mmol) with vigorous stirring. After stirring for 30 min, 4-toluenesulfonyl chloride (5.73 g, 30 mmol) was added. The mixture was stirred at RT overnight and the solvent was removed in vacuo. The residue was diluted with DCM (500 mL) and water (50 mL). The organic layer was separated, dried (MgSO4), filtered and concentrated. The crude product was purified by SiO2 chromatography eluting with a petroleum ether/EtOAc gradient (5 to 10% EtOAc) to afford 900 mg (15%) of 1-tosyl-1H-indole-4-carbaldehyde (42) as white solid: MS (ESI) m/z=300.1 [M+1]+.

Provenance & Evidence