Reaktion #92664
ord-1cff756c6f4b46999d9fa25a03a809ec
Reaktionsgleichung
Reagenzien
Lösungsmittel
Reaktionsbedingungen
Aufarbeitung
- 1Sonstigeequipped with a magnetic stirrer bar
- 2Temperaturthe mixture heated
- 3Temperaturto reflux for 40 h
- 4Waschenwashed with water (5 vol) and with brine (5 vol)
- 5Wascheneluted with methyl-tertbutyl-ether (3 vol)
- 6Sonstigethe solvent was removed under reduced pressure
Vorschrift
5,6α-epoxicholestan-3β-ol (8.9 g, 22.1 mmol, 1 eq) and tryptamine (7.1 g, 44.1 mmol, 2 eq) were charged in a round-bottomed flask equipped with a magnetic stirrer bar. 1-Butanol (70 ml, 5 vol) was added and the mixture heated to reflux for 40 h. The reaction mixture was cooled at r.t., diluted with methyl-tertbutyl-ether (5 vol) and washed with water (5 vol) and with brine (5 vol). The organic layer was passed through a silica pad (40 g) eluted with methyl-tertbutyl-ether (3 vol) then 10% Methanol/ethyl acetate (60 vol). Fractions of interest were pooled and the solvent was removed under reduced pressure to give 5α-Hydroxy-6β-(3-propylamino)-cholestan-3β-ol as a white solid (7.3 g, 59%). In same conditions, use of ethanol as solvent (40 vol) and Ca(OTf)2 as catalyst gave a 21% yield.