Piperidine → 3-Isopropylidene-4-methoxy-1,3-dihydro-indol-2-one

HRID 2416934Notes

Reaction equation

HRID 2416934 reaction equation
[CH3:1][O:2][C:3]1[CH:11]=[CH:10][CH:9]=[C:8]2[C:4]=1[CH2:5][C:6](=[O:12])[NH:7]2.N1CC[CH2:16][CH2:15][CH2:14]1>CC(C)=O>[C:15](=[C:5]1[C:4]2[C:8](=[CH:9][CH:10]=[CH:11][C:3]=2[O:2][CH3:1])[NH:7][C:6]1=[O:12])([CH3:16])[CH3:14]

Participants

4

Reactant 2

HCID 8082PiperidineHCID 5960014-Methoxy-2-indolinone

Product 1

HCID 219232453-Isopropylidene-4-methoxy-1,3-dihydro-indol-2-oneYield 19%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A mixture of 4-methoxyoxindole (3.0 g, 18.4 mmol) and piperidine (3.5 mL, 36.89 mmol) in acetone (100 mL) is heated at reflux for 18 hours. The mixture is concentrated to dryness and triturated with methanol (20 mL). Filtration removed 800 mg of unreacted 4-methoxyoxindole. The filtrate is preadsorbed on silica gel (5 g), and purified by flash chromtography (120 g SiO2, 25% ethyl acetate:hexane to 50% ethyl acetate:hexane) to provide 700 mg (19%) of 3-isopropylidene-4-methoxy-1,3-dihydro-indol-2-one. MS (ESI+) 204.

Workup

  1. temperatureis heated
  2. temperatureat reflux for 18 hours
  3. concentrationThe mixture is concentrated to dryness
  4. customtriturated with methanol (20 mL)
  5. filtrationFiltration
  6. customremoved 800 mg of unreacted 4-methoxyoxindole
  7. custompurified by flash chromtography (120 g SiO2, 25% ethyl acetate:hexane to 50% ethyl acetate:hexane)

Sources & evidence

ORD record
ord-3e560c4584014bc7b5363b76e7ba51ee
Source dataset
uspto-grants-2004_11
Patent number
US06825220B2

Reaction notes

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