Chlorosuccinimide → (3-Chloro-1H-indole-7-yl)phenylmethanone

Participants

Reaction Conditions

Reaction Steps

The 7-benzoylindole product (approximately 0.87 mole) in methylene chloride (the reaction mixture obtained in Example 2) is agitated and chilled to 15° C. in a nitrogen atmosphere. N-Chlorosuccinimide (0.87 mole) (NCS) is divided into four equal portions and added to the 7-benzoylindole-methylene chloride mixture at one-half hour intervals while maintaining the reaction temperature between 15°-20° C. One hour after the addition of the final portion of N-chlorosuccinimide, the succinimide is washed from the reaction by adding approximately 2.5 liters of water to the reaction mixture, agitating for about 15 minutes and then allowing the resulting layers to separate. The lower methylene chloride layer is drawn into another vessel and washed again with about 2.5 liters of water. The two aqueous portions are combined and extracted with about 0.2 liters of methylene chloride. This methylene chloride solution is washed with an equal volume of water. The two methylene chloride solutions are combined and distilled at a reduced pressure to a liquid temperature of approximately 80° C. The 7-benzoyl-3-chloro-indole residue obtained has a melting range of 145°-149° C.

Provenance & Evidence