Indole → HCID 67002833, compound

Participants

Reaction Conditions

Reaction Steps

To a cooled (20° C.) suspension of sodium hydride (6.59 grams, 164.74 mmol) in 20 mL of THF, was added solution of indole (6.24 grams, 53.33 mmol in 25 mL tetrahydrofuran), slowly over a period of 10 minutes, maintaining mass temperature at 25° C. under nitrogen atmosphere. The mass was diluted with tetrahydrofuran (20 mL). The reaction mixture was further stirred for 1 hour at the same temperature. Then added a solution of 2-bromo-5-chlorosulfonyl benzoic acid (20.01 grams, 66.81 mmol) in tetrahydrofuran (30 mL) slowly over a period of 10 minutes., The progress of the reaction was monitored by thin layer chromatography (TLC). After completion of the reaction, the reaction mixture was quenched onto 600 mL cold Water. The reaction mass was acidified with conc. hydrochloric acid to pH 2 and extracted with ethyl acetate (2×200 mL). The combined organic layer was washed with brine solution (2×50 mL), water (2×100 mL), dried over anhydrous sodium sulphate and concentrated under reduced pressure to obtain 17.81 grams technical product. The material was used as such in the next step, with out further purification.

Provenance & Evidence