Reacción #50101

ord-c9cb0db3d0da4374a76a3db066ad31be

Condiciones de reacción

Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    Otrofitted with a condenser and with magnetic stirring
  2. 2
    workup.ADDITION5 cm3 of the Jones reactant were introduced gently
  3. 3
    Temperaturathe reaction mixture was then heated to 45°-50° C. for 16 h
  4. 4
    workup.ADDITION(1 cm3 of Jones reactant having been added after 4 h and 2 cm3 after 9 h of reaction)
  5. 5
    OtroAt the end of reaction the Jones reactant
  6. 6
    Otrowas destroyed with 10 cm3 of isopropanol
  7. 7
    workup.ADDITIONthe mixture was diluted with 10 cm3 of water
  8. 8
    Extracciónextracted with dichloromethane
  9. 9
    Secadodried over magnesium sulfate
  10. 10
    Otrothe solvents were evaporated off
  11. 11
    Otropurified by flash chromatography

Procedimiento

0.5 g (2.26 mmol) of alcohol 1b in solution in 3 cm3 of acetone were introduced into a 10-cm3 round bottom flask fitted with a condenser and with magnetic stirring. 5 cm3 of the Jones reactant were introduced gently; the reaction was highly exothermic; the reaction mixture was then heated to 45°-50° C. for 16 h (1 cm3 of Jones reactant having been added after 4 h and 2 cm3 after 9 h of reaction). At the end of reaction the Jones reactant was destroyed with 10 cm3 of isopropanol, the mixture was diluted with 10 cm3 of water, extracted with dichloromethane and dried over magnesium sulfate, and the solvents were evaporated off. The material was incorporated onto silica and purified by flash chromatography. 0.16 g of starting alcohol 1b (32%) and 0.30 g of pure diol 3a were isolated, that was a 56% yield of compound 3a (Yld based on the unrecovered alcohol 1b=85%).

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US05424460uspto-grants-1995_06