Hydrochloric Acid → HCID 21273251, compound

Participants

Reaction Steps

A solution of N,N-dimethyl-3-(5-methyl-1H-imidazol-4-yl)-1-propanamide (300 mg) in ethanol (15 ml) was acidified (to pH 1) by the addition of ethanolic hydrogen chloride, and evaporated to yield an oil which was triturated with ether to give N,N-dimethyl-3-(5-methyl-1H-imidazol-4-yl)-1-propanamide dihydrochloride (270 mg) as a powder. This was added to a mixture of 1,7-dimethylindole (195 mg) and phosphorus oxychloride (0.15 ml) and the mixture was heated at 85° in a `closed vessel` for 1.5 h. The mixture was cooled, cold water (50 ml) was added and the suspension was stirred for 0.5 h. It was then washed with ethyl acetate (2×40 ml; discarded), basified with 2N sodium carbonate and extracted with ethyl acetate (4×80 ml). The combined, dried organic extracts were evaporated to give the free base of the title compound (232 mg) as a solid which was dissolved in hot ethanol (15 ml), and maleic acid (105 mg) in warm ethanol (5 ml) was added. The solution was evaporated and the residual solid was crystallised from ethanol (15 ml) to give the title compound (235 mg), m.p. 164°-165°.

Provenance & Evidence