Reaktion #703529

ord-62706be1eec24027b8b0a08515d82635

Reaktionsgleichung

N
ammonia
F
hydrogen fluoride
CC(=O)O[C@]1(C(C)=O)CC[C@H]2[C@@H]3CCC4=CC(=O)CC[C@]4(C)C3=CC[C@@]21C
17-acetoxy-4,9(11)-pregnadiene-3,20-dione
O=C1CCC(=O)N1Br
N-bromosuccinimide
→
CC(=O)O[C@]1(C(C)=O)CC[C@H]2[C@@H]3CCC4=CC(=O)CC[C@]4(C)[C@@]3(Br)[C@@H](F)C[C@@]21C
17-Acetoxy-9-bromo-11β-fluoro-4-pregnene-3,20-dione

Edukte

N
ammonia
F
hydrogen fluoride
CC(=O)O[C@]1(C(C)=O)CC[C@H]2[C@@H]3CCC4=CC(=O)CC[C@]4(C)C3=CC[C@@]21C
17-acetoxy-4,9(11)-pregnadiene-3,20-dione
O=C1CCC(=O)N1Br
N-bromosuccinimide

Reagenzien

Keine

Lösungsmittel

CN(C)C=O
dimethylformamide
O
water

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    SonstigeAt -78° C.
  2. 2
    FiltrationThe precipitate is filtered off
  3. 3
    Waschenwashed with water
  4. 4
    Trocknendried over sodium sulfate

Vorschrift

At -78° C., 20 ml. of hydrogen fluoride is combined with 8 ml. of dimethylformamide, and 6 g. of 17-acetoxy-4,9(11)-pregnadiene-3,20-dione (J. Org. Chem. 26 1961!: 866) and 4 g. of N-bromosuccinimide are added to the reaction mixture. The latter is allowed to stand for 3 hours at -30° C. and then introduced into a mixture of water, ice, and a 25% ammonia solution. The precipitate is filtered off, washed with water, taken up in ethyl acetate, and dried over sodium sulfate. After chromatography of the crude product on silica gel with 19-21.6% acetone/hexane, the yield is 3.0 g. of 17-acetoxy- 9-bromo-11β -fluoro-4-pregnene-3,20-dione; m.p. 180°-182° C. (under decomposition).

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US04073900uspto-grants-1978_02