4-(2-Oxopyrrolidin-1-yl)benzoic acid → Trans-4-(2-oxo-pyrrolidin-1-yl)cyclohexanecarboxylic acid

HRID 2116768Notes

Reaction equation

HRID 2116768 reaction equation
[N:1]1([C:7]2[CH:15]=[CH:14][C:10]([C:11]([OH:13])=[O:12])=[CH:9][CH:8]=2)[CH2:5][CH2:4][CH2:3][C:2]1=[O:6]>[C].[Rh].CO>[N:1]1([CH:7]2[CH2:8][CH2:9][CH:10]([C:11]([OH:13])=[O:12])[CH2:14][CH2:15]2)[CH2:5][CH2:4][CH2:3][C:2]1=[O:6]

Participants

4

Reactant 1

HCID 7731304-(2-Oxopyrrolidin-1-yl)benzoic acid

Product 1

HCID 11572026Trans-4-(2-oxo-pyrrolidin-1-yl)cyclohexanecarboxylic acidYield 94.2%

Reagents, catalysts & solvents 2

HCID 178503043HCID 178503043, compoundCatalystHCID 887MethanolSolvent

Procedure

4-(2-Pyrrolidon-1-yl)benzoic acid (20 g, 0.097 mol), 5% rhodium-carbon catalyst (6.89 g, 1.5% mol) and methanol (200 mL) are charged in an autoclave (300 mL) and stirred at room temperature for 24 hours under hydrogen pressure (9 atm, conversion rate >99%, cis:trans=75:25). The reaction solution is concentrated to 100 ml, and adjusted to pH 2 with conc. hydrochloric acid (11 g), followed by extraction with chloroform (100 mL) (×3). The organic layers are combined, washed with saturated brine (100 mL), dried over anhydrous magnesium sulfate, and the insoluble materials are removed by filtration. The resultant solution is evaporated to remove the solvent under reduced pressure. To the residue is added toluene and the precipitated crystals are collected by filtration, air-dried at 50° C. overnight to give 4-(2-pyrrolidon-1-yl)cyclohexylcarboxylic acid (19.3 g, 93.7%, cis:trans=65:35).

Workup

  1. concentrationThe reaction solution is concentrated to 100 ml
  2. extractionfollowed by extraction with chloroform (100 mL) (×3)
  3. washwashed with saturated brine (100 mL)
  4. dry with materialdried over anhydrous magnesium sulfate
  5. customthe insoluble materials are removed by filtration
  6. customThe resultant solution is evaporated
  7. customto remove the solvent under reduced pressure
  8. additionTo the residue is added toluene
  9. filtrationthe precipitated crystals are collected by filtration
  10. customair-dried at 50° C. overnight

Sources & evidence

ORD record
ord-3f2b8ef5654342889683b04b96020d5f
Source dataset
uspto-grants-2008_10
Patent number
US07439368B2

Reaction notes

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