Reaktion #92662

ord-67cba6d5fbcc4f8eade7ac5c945124b8

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Sonstigeequipped with a magnetic stirrer bar
  2. 2
    Temperaturthe mixture heated
  3. 3
    Temperaturto reflux for 40 h
  4. 4
    Waschenwashed with water (5 vol) and with brine (5 vol)
  5. 5
    Wascheneluted with methyl-tertbutyl-ether (3 vol)
  6. 6
    Sonstigethe solvent was removed under reduced pressure

Vorschrift

5,6α-epoxicholestan-3β-ol (8.9 g, 22.1 mmol, 1 eq) and putrescine (3.9 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-(4-aminobutylamino)-cholestan-3β-ol as a white solid (6.6 g, 61%). In same conditions, use of ethanol as solvent (40 vol) and Ca(OTf)2 as catalyst gave a 19% yield.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US09447141B2uspto-grants-2016_09