Réaction #502085

ord-1845d7038c7d4ac7a5d33fed45637898

Équation de réaction

[O]=[Cr](=[O])([O-])[Cl].c1cc[nH+]cc1
pyridinium chlorochromate
O=[Si]([O-])[O-].[Mg+2]
florisil
C=C(C)[C@@H]1CC[C@]2(CO)CC[C@]3(C)[C@H](CC[C@@H]4[C@@]5(C)CC[C@H](O)C(C)(C)[C@@H]5CC[C@]43C)[C@@H]12
betulin
CC(=O)[O-].[Na+]
sodium acetate
→
C=C(C)[C@@H]1CC[C@]2(C=O)CC[C@]3(C)[C@@H](CC[C@@H]4[C@@]5(C)C=CC(=O)C(C)(C)[C@@H]5CC[C@]43C)[C@@H]12
betulone aldehyde
Rendement 75.0%

Réactifs

[O]=[Cr](=[O])([O-])[Cl].c1cc[nH+]cc1
pyridinium chlorochromate
—
4A
O=[Si]([O-])[O-].[Mg+2]
florisil
C=C(C)[C@@H]1CC[C@]2(CO)CC[C@]3(C)[C@H](CC[C@@H]4[C@@]5(C)CC[C@H](O)C(C)(C)[C@@H]5CC[C@]43C)[C@@H]12
betulin
CC(=O)[O-].[Na+]
sodium acetate

Réactifs

Aucun

Solvants

ClCCl
CH2Cl2

Conditions de réaction

Conditions détaillées
See reaction.notes.procedure_details.

Traitement

  1. 1
    workup.ADDITIONTo a suspension
  2. 2
    Filtrationfiltered through a short column of silica gel
  3. 3
    AutreThe filtrate is evaporated in vacuo

Mode opératoire

To a suspension of freshly activated powdered 4A molecular sieves (1.2 g), celite (1.2 g), florisil (1.2 g), sodium acetate (500 mg) and pyridinium chlorochromate (1.2 g) in CH2Cl2 (25 mL) add betulin (500 mg). The mixture is to be stirred for 2 hrs, and then filtered through a short column of silica gel. The filtrate is evaporated in vacuo. The residue is then subjected to column chromatography to afford betulone aldehyde (370 mg) as white solid.

Source

DOI: 10.6084/m9.figshare.5104873.v1Brevet: US08088757B2uspto-grants-2012_01