Ammonium formate → (R,S)-Equol

HRID 642927Notes

Reaction equation

HRID 642927 reaction equation
CC([O:4][C:5]1[CH:10]=[CH:9][C:8]([C:11]2[C:16](=O)[C:15]3[CH:18]=[CH:19][C:20]([O:22]C(C)=O)=[CH:21][C:14]=3[O:13][CH:12]=2)=[CH:7][CH:6]=1)=O.C([O-])=O.[NH4+]>[OH-].[OH-].[Pd+2].C(O)(=O)C>[CH2:16]1[C:15]2[CH:18]=[CH:19][C:20]([OH:22])=[CH:21][C:14]=2[O:13][CH2:12][CH:11]1[C:8]1[CH:9]=[CH:10][C:5]([OH:4])=[CH:6][CH:7]=1

Participants

5

Reactant 2

HCID 2723923Ammonium formateHCID 10359753Daidzein diacetate

Product 1

HCID 382975(R,S)-EquolYield 83.4%

Reagents, catalysts & solvents 2

HCID 9942167Palladium hydroxideCatalystHCID 176Acetic AcidSolvent

Procedure

A 250-ml round bottom flask was equipped with reflux condenser, heating mantle, and magnetic stirrer, and was charged with 8.15 grams of daidzein diacetate (0.024 mole), 100 ml of acetic acid, 20 grams of ammonium formate (31 mole), and 5.0 grams of commercial Pearlman's catalyst. The mixture was stirred at relfux for 1.4 hours, at which time thin-layer chromatographic analysis indicated consumption of the starting material. The reaction mixture was cooled to room temperature, diluted with 100 ml of ethyl acetate, and filtered through a pad of diatomaceous earth filter aid. The resulting clear filtrate was poured into about 500 ml of water and shaken. The layers were allowed to separate and the top organic layer was separated, washed with water and then with 5% aqueous sodium bicarbonate solution to remove residual acetic acid. (The acetamide by-product is extracted into the water layers during this procedure.) The resulting clear solution was stripped of ethyl acetate under reduced pressure to give an off-white solid product. This material was triturated with about 15 ml of chloroform and the resulting white solid product filtered off and air-dried to afford 4.85 grams of (+/−)-equol (83.2% yield). The product was analyzed by IR and proton NMR spectroscopy and found to be of greater then 95% purity.

Workup

  1. customA 250-ml round bottom flask was equipped
  2. temperaturewith reflux condenser
  3. temperatureheating mantle
  4. customconsumption of the starting material
  5. additiondiluted with 100 ml of ethyl acetate
  6. filtrationfiltered through a pad of diatomaceous earth
  7. filtrationfilter aid
  8. additionThe resulting clear filtrate was poured into about 500 ml of water
  9. stirringshaken
  10. customto separate
  11. customthe top organic layer was separated
  12. washwashed with water
  13. customwith 5% aqueous sodium bicarbonate solution to remove residual acetic acid
  14. extraction(The acetamide by-product is extracted into the water layers during this procedure
  15. customto give an off-white solid product
  16. customThis material was triturated with about 15 ml of chloroform
  17. filtrationthe resulting white solid product filtered off
  18. customair-dried

Sources & evidence

ORD record
ord-ac12f2a43ebb4187949fd985e43f5f4f
Source dataset
uspto-grants-2010_04
Patent number
US07696363B2

Reaction notes

Loading…