Potassium Carbonate → (3RS)-3-Methyl-4-N-(3-methyl-2-buten-1-yl)-3,4-dihydroquinoxalin-2(1H)-one

HRID 840565Notes

Reaction equation

HRID 840565 reaction equation
[CH3:1][CH:2]1[NH:11][C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[NH:4][C:3]1=[O:12].[CH3:13][C:14]([CH3:18])=[CH:15][CH2:16]Br.C(=O)([O-])[O-].[K+].[K+]>CN(C)C=O.C(OCC)(=O)C>[CH3:1][CH:2]1[N:11]([CH2:16][CH:15]=[C:14]([CH3:18])[CH3:13])[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[NH:4][C:3]1=[O:12]

Participants

6

Reactant 3

HCID 11430Potassium CarbonateHCID 700922-Butene, 1-bromo-3-methyl-HCID 27636423-Methyl-3,4-dihydroquinoxalin-2(1H)-one

Product 1

HCID 22619802(3RS)-3-Methyl-4-N-(3-methyl-2-buten-1-yl)-3,4-dihydroquinoxalin-2(1H)-oneYield 84%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Procedure

(3RS)-3-Methyl-3,4-dihydroquinoxalin-2(1H)-one (4.86 g, 0.03 mol) dissolved in 50 ml of N,N-dimethylformamide, was alkylated with 4.2 ml (0.033 mol) of 3-methyl-2-buten-1-yl bromide (90%) in the presence of 4.60 g (0.033 mol) of pulverulent potassium carbonate. The reaction mixture was stirred at room temperature until reaction of the educt was complete. The solvent was then stripped off in vacuo, the residue was taken up in ethyl acetate and water, the phases were separated, the aqueous phase was extracted twice with ethyl acetate, and the combined organic extracts were washed twice with water. Drying over sodium sulfate, concentration in vacuo and crystallization from pentane gave 5.80 g (84%) of white crystalline product of melting point 92-93° C.

Workup

  1. customwater, the phases were separated
  2. extractionthe aqueous phase was extracted twice with ethyl acetate
  3. washthe combined organic extracts were washed twice with water
  4. dry with materialDrying over sodium sulfate, concentration in vacuo and crystallization from pentane

Sources & evidence

ORD record
ord-bc154d2bc21d48e593c4f5cddd4ae223
Source dataset
uspto-grants-2002_04
Patent number
US06369057B1

Reaction notes

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