Iodine → 3-iodo-5-(6-isopropoxypyrazin-2-yl)-1H-indole

Participants

Reaction Steps

To a solution of 5-(6-isopropoxy-pyrazin-2-yl)-1H-indole (32 g, 0.126 mol) in DMF (250 mL) was added KOH (17.8 g, 0.316 mol) and then stirred for 15 min at RT. I2 (35.3 g, 0.139 mol) was added to the reaction mixture and stirred at RT for another 1 h. Then reaction mixture was poured into ice water and excess of I2 was quenched with sodium thiosulfite. The resulting solid was collected by filtration, washed with water and dried under vacuum to afford crude 3-iodo-5-(6-isopropoxypyrazin-2-yl)-1H-indole (49 g) as pale brown solid. MS (ESI, m/z): 379.9 (M+1). This material was used to further step without purification.

Provenance & Evidence