反应详情

C-(1H-Indol-3-yl)-methylamine (292 mg, 2 mmol.) and 4-dimethylamino-4-phenylcyclohexanecarbaldehyde (463 mg, 2 mmol.) were dissolved, under argon, in abs. 1,2-dichloroethane (20 ml). Sodium triacetoxyborohydride (600 mg, 2.8 mmol.) was added to this mixture, and stirring was carried out for 24 h at RT. For working up, the mixture was concentrated and 1M HCl (20 ml) and ether (40 ml) were added thereto. The aqueous phase was washed with ether (2×20 ml), adjusted to pH 11 with 5M NaOH, diluted with water (10 ml) and extracted with EE (3×20 ml). The combined EE extracts were dried, filtered and concentrated. The resulting crude product, a mixture of the two diastereoisomeric target compounds, was purified by chromatography on silica gel with methanol/conc. ammonia solution (500:1) and separated. The non-polar diastereoisomer of (4-{[(1H-indol-3-ylmethyl)amino]methyl}-1-phenylcyclohexyl)dimethylamine dihydrochloride could be obtained in the form of a brown oil in a yield of 83 mg. The oil was dissolved in 2-butanone (5 ml); chlorotrimethylsilane (72 μl, 0.56 mmol.) was added thereto, and stirring was carried out for 2 h at RT. The resulting solid was filtered off with suction. The dihydrochloride of the non-polar diastereoisomer of (4-{[(1H-indol-3-ylmethyl)amino]methyl}-1-phenylcyclohexyl)dimethylamine could thus be obtained in a yield of 48 mg (white solid, m.p. 181–183° C.).

1. concentrationthe mixture was concentrated
2. addition1M HCl (20 ml) and ether (40 ml) were added
3. washThe aqueous phase was washed with ether (2×20 ml)
4. additiondiluted with water (10 ml)
5. extractionextracted with EE (3×20 ml)
6. customThe combined EE extracts were dried
7. filtrationfiltered
8. concentrationconcentrated
9. additionThe resulting crude product, a mixture of the two diastereoisomeric target compounds
10. customwas purified by chromatography on silica gel with methanol/conc
11. customammonia solution (500:1) and separated