Réaction #554632

ord-216673b50fbd4ea9b552ac6260d82140

Équation de réaction

CC(=O)[O][Na]
CH3COONa
C[C@@H]1CC[C@@]2(OC1)O[C@H]1C[C@H]3[C@@H]4CC[C@H]5C[C@@H](O)CC[C@]5(C)[C@H]4CC[C@]3(C)[C@H]1[C@@H]2C
1
C[C@@H]1CC[C@@]2(OC1)O[C@H]1C[C@H]3[C@@H]4CC[C@H]5C[C@@H](O)CC[C@]5(C)[C@H]4CC[C@]3(C)[C@H]1[C@@H]2C
tigogenin
CC(C)=O
CH3COCH3
CC(=O)O
CH3COOH
→
CC(=O)O[C@H]1CC[C@@]2(C)[C@@H](CC[C@@H]3[C@@H]2CC[C@]2(C)C(C(C)=O)=CC[C@@H]32)C1
2
Rendement 69.5%
CC(=O)O[C@H]1CC[C@@]2(C)[C@@H](CC[C@@H]3[C@@H]2CC[C@]2(C)C(C(C)=O)=CC[C@@H]32)C1
3β-Acetoxy-5α-pregn-16-en-20-one
Rendement 69.5%

Réactifs

—
CrO3
CC(=O)[O][Na]
CH3COONa
C[C@@H]1CC[C@@]2(OC1)O[C@H]1C[C@H]3[C@@H]4CC[C@H]5C[C@@H](O)CC[C@]5(C)[C@H]4CC[C@]3(C)[C@H]1[C@@H]2C
1
C[C@@H]1CC[C@@]2(OC1)O[C@H]1C[C@H]3[C@@H]4CC[C@H]5C[C@@H](O)CC[C@]5(C)[C@H]4CC[C@]3(C)[C@H]1[C@@H]2C
tigogenin
CC(C)=O
CH3COCH3
CC(=O)O
CH3COOH

Réactifs

[Cl][Ti]([Cl])([Cl])[Cl]
TiCl4

Solvants

CC(C)O
isopropanol
O
water
CC(=O)OC(C)=O
(CH3CO)2O
O
water
CC(=O)OC(C)=O
(CH3CO)2O

Conditions de réaction

Température
100°CELSIUS
Conditions détaillées
See reaction.notes.procedure_details.

Traitement

  1. 1
    workup.WAITboiled an additional 2 h
  2. 2
    Températurecooled to 40° C.
  3. 3
    workup.STIRRINGstirred 20 min
  4. 4
    Températurecooled to room temperature
  5. 5
    workup.STIRRINGstirred an additional hour
  6. 6
    Températuregradually heated
  7. 7
    workup.DISTILLATIONto distill off acetone
  8. 8
    Autrea temperature of 115-117° C.
  9. 9
    workup.WAITboiled for 1.5 h
  10. 10
    Températurecooled to room temperature
  11. 11
    workup.ADDITIONtreated with water (425 mL)
  12. 12
    FiltrationThe resulting precipitate was filtered off
  13. 13
    Lavagewashed with water
  14. 14
    Autrerecrystallized from methanol:acetone (3:1)

Mode opératoire

A mixture of 1 (50 g, 120.0 mmol), (CH3CO)2O (150 mL), and C5H5N (10 mL) was boiled for 1 h, cooled to 100° C., stirred, treated with TiCl4 (2.5 g, 13.16 mmol) in (CH3CO)2O (2.5 mL), boiled an additional 2 h, cooled to 40° C., treated gradually with CH3COONa (10 g) dissolved in water (25 mL), stirred 20 min, cooled to room temperature, poured into CH3COCH3 (220 mL) and CH3COOH (220 mL), oxidized by addition of CrO3 (15 g) in water (7.5 mL) at 15-18° C., stirred an additional hour, treated with isopropanol (7.5 mL), gradually heated to distill off acetone and reach a temperature of 115-117° C., boiled for 1.5 h, cooled to room temperature, and treated with water (425 mL). The resulting precipitate was filtered off, washed with water, and recrystallized from methanol:acetone (3:1) to afford 2 (29 g, 69.5%), mp 158-162° C., lit. mp 158-162° C. [2].

Source

DOI: 10.6084/m9.figshare.5104873.v1Brevet: US08623849B2uspto-grants-2014_01