4-Toluenesulfonyl chloride → 3-iodo-5-(6-isopropoxypyrazin-2-yl)-1-tosyl-1H-indole

Participants

Reaction Steps

To a solution of 3-iodo-5-(6-isopropoxy-pyrazin-2-yl)-1H-indole (20 g, 0.053 mol) in DMF (200 mL) was added NaH (6.5 g, 0.158 mol) slowly at 0° C., and then stirred for 15 min. p-Toluenesulfonyl chloride (15.10 g, 0.079 mol) was added slowly to the reaction mixture and stirred for 1 h. The resulting mixture was poured into ice with stirring and the precipitate was formed. The resulting precipitate was collected by filtration, washed with water and dried under vacuum to give the crude product. The crude product was purified by column chromatography eluting with EtOAc and n-hexane to afford the desire 3-iodo-5-(6-isopropoxypyrazin-2-yl)-1-tosyl-1H-indole (15.5 g, 55%) as pale brown solid. MS (ESI, m/z): 533.6 (M+1).

Provenance & Evidence