反応 #502085

ord-1845d7038c7d4ac7a5d33fed45637898

反応方程式

[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
収率 75.0%

反応物

[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

試薬

なし

溶媒

ClCCl
CH2Cl2

反応条件

詳細条件
See reaction.notes.procedure_details.

後処理

  1. 1
    workup.ADDITIONTo a suspension
  2. 2
    ろ過filtered through a short column of silica gel
  3. 3
    その他The filtrate is evaporated in vacuo

実験手順

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.

出典

DOI: 10.6084/m9.figshare.5104873.v1特許: US08088757B2uspto-grants-2012_01