O-Phenylenediamine → 2(1H)-Quinoxalinone, 3,4-dihydro-

HRID 1771968Notes

Reaction equation

HRID 1771968 reaction equation
[C:1]1([NH2:8])[C:2]([NH2:7])=[CH:3][CH:4]=[CH:5][CH:6]=1.C(N(CC)CC)C.Br[CH2:17][C:18](OCC)=[O:19]>CN(C=O)C.CCOC(C)=O.O>[NH:7]1[C:2]2[C:1](=[CH:6][CH:5]=[CH:4][CH:3]=2)[NH:8][CH2:17][C:18]1=[O:19]

Participants

7

Reactant 3

HCID 7243O-PhenylenediamineHCID 7748Ethyl bromoacetateHCID 8471Triethylamine

Product 1

HCID 1859492(1H)-Quinoxalinone, 3,4-dihydro-

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
120 °C

Procedure

To a solution of benzene-1,2-diamine (150 g, 1387 mmol) and triethylamine (193 mL, 1387 mmol) in DMF (Ratio: 20 times, Volume: 3000 mL) was added ethyl bromoacetate (232 g, 1387 mmol). The reaction mixture was heated at 120° C. for 36 h. The reaction mixture was cooled to room temperature and diluted with EtOAc and water. The organic layer was separated and washed with brine, dried over Na2SO4, filtered, and concentrated to give crude material. The crude product was purified via ISCO, eluted with 50% EtOAC/hexane to afford 3,4-dihydroquinoxalin-2(1H)-one, Intermediate E-1A (140 g, 945 mmol, 68.1%). 1H NMR (400 MHz, CDCl3) δ ppm 7.7 (1H, bs), 6.9 (1H, m), 6.75 (1H, m), 6.70 (2H, m), 4.0 (1H, s), 3.85 (1H, bs).

Workup

  1. temperatureThe reaction mixture was cooled to room temperature
  2. customThe organic layer was separated
  3. washwashed with brine
  4. dry with materialdried over Na2SO4
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customto give crude material
  8. customThe crude product was purified via ISCO
  9. washeluted with 50% EtOAC/hexane

Sources & evidence

ORD record
ord-052411a33e7941329ac078b41ebd58cb
Source dataset
uspto-grants-2016_02
Patent number
US09249157B2

Reaction notes

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