Diisopropylethylamine → 4-(4-Benzyl-piperazin-1-yl)-1H-indole

Participants

Reaction Conditions

Reaction Steps

A mixture of 500 mg (3.78 mmole) 1H-indol-4-yl-amine, 993 mg (3.78 mmole) N-benzyl-bis(2-chloroethyl)amine hydrochloride, and 1.32 mL (7.6 mmole) diisopropylethylamine in 10 mL chlorobenzene was heated at 130° C. for 24 hours. Another 0.66 mL (3.8 mmole) diisopropylethylamine was added and the mixture was heated at 130° C. for an additional 5 hours. The mixture was partitioned between 25 mL ethyl acetate and 10 mL 5% sodium hydroxide. The organic phase was extracted with 10 mL 3 N hydrochloric acid. The aqueous phase was washed with 15 mL ethyl ether, then made basic with 50% sodium hydroxide. The product was extracted with 25 mL dichloromethane, the organic phase was washed with 10 mL water, dried (magnesium sulfate) and concentrated under reduced pressure. 4-(4-benzyl-piperazin-1-yl)-1H-indole (274 mg) was isolated as the hydrochloride salt from ethyl ether.

Provenance & Evidence