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

HRID 1899913Notes

Reaction equation

HRID 1899913 reaction equation
BrCC([O:5][CH2:6][CH3:7])=O.[C:8]1([NH2:15])[CH:13]=[CH:12][CH:11]=[CH:10][C:9]=1[NH2:14].C(N(CC)CC)C>C1COCC1.C(Cl)Cl>[NH:14]1[C:9]2[C:8](=[CH:13][CH:12]=[CH:11][CH:10]=2)[NH:15][CH2:7][C:6]1=[O:5]

Participants

6

Reactant 3

HCID 7243O-PhenylenediamineHCID 7748Ethyl bromoacetateHCID 8471Triethylamine

Product 1

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

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

A solution of ethyl bromoacetate (III, 13.3 ml) in THF (50 ml) is added over 2 hr to a stirred solution of 1,2-phenylenediamine (II, 10.0 g) and triethylamine (16.8 ml) in THF (22 ml) and methylene chloride (22 ml). The mixture is heated at 60° for 3 hr, and is concentrated. The resulting solids are suspended and shaken vigorously in hexane (250 ml) and water (150 ml). The hexane layer is decanted, and the process is repeated with two additional 250 ml portions of hexane. The solids are filtered, dried and recrystallized from methylene chloride/hexane to give the desired product as a solid. The concentrated filtrate is purified by flash chromatography eluting with ethyl acetate/methylene chloride (25/75) to give additional title compound, mp 135°-136°: NMR (CDCl3) 8.30, 6.85-6.95, 6.65-6.80, 4.00 and 3.86 δ.

Workup

  1. temperatureThe mixture is heated at 60° for 3 hr
  2. concentrationis concentrated
  3. customThe hexane layer is decanted
  4. filtrationThe solids are filtered
  5. customdried
  6. customrecrystallized from methylene chloride/hexane

Sources & evidence

ORD record
ord-a39492edc61a4143850347f9cccc2d52
Source dataset
uspto-grants-1996_11
Patent number
US05574038

Reaction notes

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