Iodo benzene diacetate → (5S)-1-{[(1,1-dimethylethyl)oxy]carbonyl}-4,5-dihydro-1H-pyrazole-5-carboxylic acid

HRID 1396869Notes

Reaction equation

HRID 1396869 reaction equation
[CH3:1][C:2]([O:5][C:6]([N:8]1[C@H:12]([C:13]([OH:15])=[O:14])[CH2:11][CH2:10][NH:9]1)=[O:7])([CH3:4])[CH3:3].C(O)(=O)C.C(O)(=O)C.IC1C=CC=CC=1>CO>[CH3:4][C:2]([O:5][C:6]([N:8]1[C@H:12]([C:13]([OH:15])=[O:14])[CH2:11][CH:10]=[N:9]1)=[O:7])([CH3:1])[CH3:3]

Participants

4

Reactant 2

HCID 12217721Iodo benzene diacetateHCID 58501748(S)-2-(tert-Butoxycarbonyl)pyrazolidine-3-carboxylic acid

Product 1

HCID 68287959(5S)-1-{[(1,1-dimethylethyl)oxy]carbonyl}-4,5-dihydro-1H-pyrazole-5-carboxylic acidYield 64%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a 50 ml round bottom flask was added (3S)-2-{[(1,1-dimethylethyl)oxy]carbonyl}-3-pyrazolidinecarboxylic acid (431 mg, 1.99 mmol) in methanol (15 mL), followed by iodobenzene diacetate (770 mg, 2.39 mmol). The mixture was stirred at room temperature for 10 min, and LCMS indicated the reaction was complete. The organic solvent was removed under vacuum, and the residue was taken up in 1 M aq. NaHCO3 (30 mL). The aqueous mixture was washed with DCM (3×20 mL), acidified with 6 N HCl to ˜pH 2.0, and then extracted with DCM (3×30 mL). The combined organic extracts were dried (Na2SO4), filtered, and concentrated under vacuum to afford (5S)-1-{[(1,1-dimethylethyl)oxy]carbonyl}-4,5-dihydro-1H-pyrazole-5-carboxylic acid (273 mg, 1.27 mmol, 64% yield) as a clear oil.

Workup

  1. customThe organic solvent was removed under vacuum
  2. washThe aqueous mixture was washed with DCM (3×20 mL)
  3. extractionextracted with DCM (3×30 mL)
  4. dry with materialThe combined organic extracts were dried (Na2SO4)
  5. filtrationfiltered
  6. concentrationconcentrated under vacuum

Sources & evidence

ORD record
ord-40e4be92484a4e949eaa4f64f196ad08
Source dataset
uspto-grants-2014_12
Patent number
US08901119B2

Reaction notes

Loading…