4-(5-chloro-[1H]-indol-3-yl)-piperidine → HCID 10327255, compound

Participants

Reaction Steps

The diastereoisomer mixture of (4-dimethylamino-4-phenylcyclohexylmethyl)-carbamic acid phenyl ester (774 mg, 2.2 mmole) was added to the suspension of 5-chloro-3-piperidine-4-yl-1H-indole (516 mg, 2.2 mmole) in dioxane (20 ml). The reaction mixture was a suspension also at 100° C., and was boiled under reflux for 40 hours. To work up the suspension the existing precipitate was filtered off, washed with dioxane (1×1 ml) and diethyl ether (3×2 ml) and dried in vacuo. The isolated solid (183 mg, 17%, m.p. 140°-150° C.) was a still unpurified part of the polar diastereoisomer of 4-(5-chloro-1H-indol-3-yl)piperidine-1-carboxylic acid-(4-dimethylamino-4-phenylcyclohexylmethyl)-amide, which was purified by flash chromatography on silica gel [20 g, eluent: methanol (500 ml)]. The mother liquor and the wash phases were concentrated by evaporation in vacuo. The residue contained in addition to phenol, also the two diastereoisomers of 4-(5-chloro-1H-indol-3-yl)piperidine-1-carboxylic acid-(4-dimethylamino-4-phenylcyclohexylmethyl)-amide. The diastereoisomers were separated and purified by flash chromatography on silica gel (75 g). Methanol/EE (1:1; 900 ml) was used as eluent. The non-polar diastereoisomer (335 mg, m.p. 205°-207° C., 31%) and the polar diastereoisomer of 4-(5-chloro-1H-indol-3-yl)piperidine-1-carboxylic acid-(4-dimethylamino-4-phenylcyclohexylmethyl)-amide (115 mg, m.p. 140°-143° C., 11%) were thereby obtained as pale yellow solids.

Provenance & Evidence