Reaktion #1663973

ord-3b3bea7058c44df4a69d3924b0431d53

Reaktionsgleichung

CC(=O)[C@H]1CC[C@H]2[C@@H]3CC[C@H]4C[C@H](O)[C@@H](C)C[C@]4(C)[C@H]3C(=O)C[C@]12C
3α-hydroxy-2β-methyl-5α-pregnane-11,20-dione
BrBr
bromine
→
C[C@H]1C[C@@]2(C)[C@@H](CC[C@H]3[C@@H]4CC[C@H](C(=O)CBr)[C@@]4(C)CC(=O)[C@@H]32)C[C@@H]1O
title compound
C[C@H]1C[C@@]2(C)[C@@H](CC[C@H]3[C@@H]4CC[C@H](C(=O)CBr)[C@@]4(C)CC(=O)[C@@H]32)C[C@@H]1O
21-Bromo-3α-hydroxy-2β-methyl-5α-pregnane-11,20-dione

Edukte

CC(=O)[C@H]1CC[C@H]2[C@@H]3CC[C@H]4C[C@H](O)[C@@H](C)C[C@]4(C)[C@H]3C(=O)C[C@]12C
3α-hydroxy-2β-methyl-5α-pregnane-11,20-dione
BrBr
bromine

Reagenzien

Keine

Lösungsmittel

CO
methanol
CO
methanol

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    SonstigeThe reaction mixture was partitioned between ethyl acetate and water
  2. 2
    Sonstigethe organic layer was separated
  3. 3
    Waschenwashed with water
  4. 4
    Trocknendried (MgSO4)
  5. 5
    Sonstigeevaporated to a white foam
  6. 6
    Sonstigepurification by preparative t.l.c

Vorschrift

A solution of 3α-hydroxy-2β-methyl-5α-pregnane-11,20-dione (1.04g.) in dry methanol (150ml) was stirred at 0°-5° during the dropwise addition of a solution of bromine (0.16ml) in dry methanol (20ml) over a period of 2.5 hours. The reaction mixture was partitioned between ethyl acetate and water and the organic layer was separated, washed with water, dried (MgSO4) and evaporated to a white foam; purification by preparative t.l.c. (ethyl acetate: benzene 1:2.5) gave the title compound (510mg.), m.p. 140° dec.; [α]D + 133° (c 0.95).

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US03983111uspto-grants-1976_09