Water → HCID 21397137, compound

Participants

Reaction Steps

To a solution of 2-[3-(4-methyl-1-piperazinyl)propylamino]-5-chloroaniline (70 g., 0.248 mole) in 350 ml. of water and 150 ml. ethanol was added, with stirring, 59.0 g. (0.557 mole) of cyanogen bromide in portions over 1 hour. The temperature was maintained at 40°-50° C. After the addition was completed the mixture was allowed to cool to room temperature and stirred overnight. After pouring into 1500 ml. ice water and making strongly alkaline with 20% NaOH, the precipitated solid was collected on a Buchner funnel, washed with water and dried in the vacuum oven to obtain 45.0 g. (59% yield) of crude 1-[3-(4-methyl-1-piperazinyl)propyl]-2-amino-5-chlorobenzimidazole, m.p. 223°-227° C. A portion was recrystallized from acetone as colorless needles, m.p. 228°-229.5° C.

Provenance & Evidence