Hydrochloric Acid → 3-{4-[(2-Diethylaminoethyl)aminomethyl]phenyl}-1,4-dihydroindeno[1,2-c]pyrazole trihydrochloride

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Reaction Steps

A mixture of N-(2-diethylaminoethyl)-4-(1,4-dihydroindeno[1,2-c]pyrazol-3-yl)benzamide (2.75 g, Example 29) and dry tetrahydrofuran (100 ml) was stirred at room temperature under nitrogen and lithium aluminium hydride (3.4 g) was added portionwise. The reaction mixture was then boiled under reflux for about 2.5 hours, then cooled in an ice/water bath. Ethyl acetate (100 ml) and water (100 ml) were added. Then the organic phase was separated off, washed with brine (25 ml), dried, filtered and evaporated to give a yellow oil. The oil was purified by flash column chromatography on silica using ethyl acetate/ ethanol/ triethylamine (7:2:1) as eluant to give a pale yellow gum. The gum was dissolved in warm ethanol (5 ml), hydrochloric acid (conc, 0.6 ml) was added and the solvent then removed under reduced pressure. The gummy solid residue was boiled up with ethanol (10 ml) and cooled in ice. The precipitated solid was collected by filtration, washed with ethanol and dried to give 3-{4-[(2-diethylaminoethyl)aminomethyl]phenyl}-1,4-dihydroindeno[1,2-c]pyrazole trihydrochloride, m.p. 225° C.

Provenance & Evidence