Iodine → 1-ethyl-2-iodo-6-methoxy-1H-indole-3-carbonitrile

Participants

Reaction Conditions

Reaction Steps

A 2M solution of lithium diisopropyl amide in THF/hexanes (Acros) (3.9 mL, 7.8 mmol) is diluted with THF (5 mL) in a flame-dried flask. After cooling the reaction to −30° C., a solution of 1-ethyl-6-methoxy-1H-indole-3-carbonitrile (1.30 g, 6.5 mmol) in THF (10 mL) is added dropwise during 10 min, maintaining the temperature at −30° C. After stirring for an additional 30 min at this temperature, a solution of iodine (2.31 g, 9.1 mmol) in THF (5 mL) is added during 10 min. After the addition, the reaction is warmed to ambient temperature during 1 h. The reaction is then diluted with ice-H2O and extracted with EtOAc (2×). The combined organic phases are washed with 1M sodium thiosulfate and saturated NaCl and then concentrated to a brown solid. Chromatography (CH2Cl2/hexanes, 1/1) over silica gel gives 1.31 g (62%) of 1-ethyl-2-iodo-6-methoxy-1H-indole-3-carbonitrile as an off-white solid.

Provenance & Evidence