Water → Pregna-4,20-dien-3,6-dione

HRID 1604284Notes

Reaction equation

HRID 1604284 reaction equation
[CH2:1]=[CH:2][C@@H:3]1[C@:20]2([CH3:21])[C@H:6]([C@H:7]3[C@H:17]([CH2:18][CH2:19]2)[C@:15]2([CH3:16])[C:10]([CH2:11][C@@H:12]([OH:22])[CH2:13][CH2:14]2)=[CH:9][CH2:8]3)[CH2:5][CH2:4]1.CC(C)=[O:25].OS(O)(=O)=O.O=[Cr](=O)=O.CC(O)C.O>CC(C)=O>[CH2:1]=[CH:2][C@@H:3]1[C@:20]2([CH3:21])[C@H:6]([C@H:7]3[C@H:17]([CH2:18][CH2:19]2)[C@:15]2([CH3:16])[C:10](=[CH:11][C:12](=[O:22])[CH2:13][CH2:14]2)[C:9](=[O:25])[CH2:8]3)[CH2:5][CH2:4]1

Participants

6

Reactant 4

HCID 962WaterHCID 3776IsopropanolHCID 14263442PregnadienolHCID 131709961Jones' reagent2×

Product 1

HCID 15429665Pregna-4,20-dien-3,6-dione

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A solution of pregna-5,20-dien-3β-ol (300.5 mg, 1.000 mmol) in 35 mL of acetone was cooled in an ice water bath and 2.67 M Jones reagent (0.71 mL, 1.9 mmol) was added. After stirring 11/2 h a further 0.71 mL of Jones reagent were added and the reaction was continued 45 min, 2-Propanol (1.0 mL) was added and the mixture was poured into 100 mL of water. The mixture was then extracted twice with 50 mL of ethyl acetate and the combined organic extracts were washed with 50 mL of saturated sodium bicarbonate +50 mL of water +50 mL of brine and filtered through a 21 mm dia×22 mm high column of silica gel 60. The column was eluted further with 25 mL of ethyl acetate and the combined filtrates were concentrated under reduced pressure. Recrystallization of the residue from 95% ethanol gave a light yellow powder (104.6 mg, 0.3348 mmol 33%), m.p. 114-120° C.

Workup

  1. additionwere added
  2. extractionThe mixture was then extracted twice with 50 mL of ethyl acetate
  3. washthe combined organic extracts were washed with 50 mL of saturated sodium bicarbonate +50 mL of water +50 mL of brine
  4. filtrationfiltered through a 21 mm dia×22 mm high column of silica gel 60
  5. washThe column was eluted further with 25 mL of ethyl acetate
  6. concentrationthe combined filtrates were concentrated under reduced pressure
  7. customRecrystallization of the residue from 95% ethanol
  8. customgave a light yellow powder (104.6 mg, 0.3348 mmol 33%), m.p. 114-120° C.

Sources & evidence

ORD record
ord-1b2eabf488484f5b8c0cafcaffc14a03
Source dataset
uspto-grants-1999_11
Patent number
US05994333

Reaction notes

Loading…