反应 #502085

ord-1845d7038c7d4ac7a5d33fed45637898

反应方程式

[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
收率 75.0%

反应物

[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

试剂

无

溶剂

ClCCl
CH2Cl2

反应条件

详细条件
See reaction.notes.procedure_details.

后处理

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

实验过程

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.

来源

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