(3,4-Dimethoxyphenyl)acetic acid → HCID 22315298, compound

HRID 430359Notes

Reaction equation

HRID 430359 reaction equation
C([N-]C(C)C)(C)C.[Li+].[CH3:9][O:10][C:11]1[CH:12]=[C:13]([CH2:19][C:20]([OH:22])=[O:21])[CH:14]=[CH:15][C:16]=1[O:17][CH3:18].I[CH2:24][CH:25]1[CH2:29][CH2:28][CH2:27][CH2:26]1>O1CCCC1.CN1CCCN(C)C1=O.CN1CCCN(C)C1=O>[CH:25]1([CH2:24][CH:19]([C:13]2[CH:14]=[CH:15][C:16]([O:17][CH3:18])=[C:11]([O:10][CH3:9])[CH:12]=2)[C:20]([OH:22])=[O:21])[CH2:29][CH2:28][CH2:27][CH2:26]1

Participants

6

Reactant 3

HCID 7139(3,4-Dimethoxyphenyl)acetic acidHCID 2724682Lithium diisopropylamideHCID 2762531(Iodomethyl)cyclopentane

Product 1

HCID 22315298HCID 22315298, compoundYield 63.9%

Reagents, catalysts & solvents 2

HCID 816462(1H)-Pyrimidinone, tetrahydro-1,3-dimethyl-SolventHCID 22565281tetrahydrofuran 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinoneSolvent

Conditions

Temperature
25 °C

Procedure

A solution of freshly prepared lithium diisopropylamide (58.5 mL of a 0.91M stock solution, 53.2 mmol) cooled to −78° C. was treated with (3,4-dimethoxy-phenyl)-acetic acid (4.97 g, 25.3 mmol) in tetrahydrofuran/1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (25.3 mL, 3:1). The resulting solution was stirred at −78° C. for 45 min and at 25° C. for 15 min. At this time, the reaction was cooled to 0° C. and was treated with a solution of iodomethylcyclopentane (5.87 g, 27.8 mmol) in 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (1 mL). The reaction mixture was stirred at 0° C. for 30 min. The reaction was then warmed to 25° C. and was stirred at 25° C. for 18 h. The reaction mixture was then quenched by the dropwise addition of saturated aqueous ammonium chloride solution (10 mL). The resulting mixture was concentrated in vacuo. The residue was diluted with water (100 mL) and acidified to pH=1 with a 1N aqueous hydrochloric acid solution. This solution was extracted with ethyl acetate (3×50 mL). The organics were washed with a saturated aqueous lithium chloride solution (1×100 mL), dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 70/30 hexanes/ethyl acetate) afforded 3-cyclopentyl-2-(3,4-dimethoxy-phenyl)-propionic acid (4.5 g, 63.8%) as a yellow solid: mp 111-112° C.; EI-HRMS m/e calcd for C16H22O4 (M+) 278.1518 found 278.1517.

Workup

  1. temperatureAt this time, the reaction was cooled to 0° C.
  2. stirringThe reaction mixture was stirred at 0° C. for 30 min
  3. temperatureThe reaction was then warmed to 25° C.
  4. stirringwas stirred at 25° C. for 18 h
  5. customThe reaction mixture was then quenched by the dropwise addition of saturated aqueous ammonium chloride solution (10 mL)
  6. concentrationThe resulting mixture was concentrated in vacuo
  7. additionThe residue was diluted with water (100 mL)
  8. extractionThis solution was extracted with ethyl acetate (3×50 mL)
  9. washThe organics were washed with a saturated aqueous lithium chloride solution (1×100 mL)
  10. dry with materialdried over sodium sulfate
  11. filtrationfiltered
  12. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-443626b1baac4fb19b4c1e748ccf18df
Source dataset
uspto-grants-2001_11
Patent number
US06320050B1

Reaction notes

Loading…