Water → 9-(2-Methoxyethoxy)-9H-indeno[1,2-b]pyrazine-2,3(1H, 4H)-dione

HRID 129452

Reaction equation

HRID 129452 reaction equation
[OH:1][CH:2]1[C:14]2[NH:13][C:12](=[O:15])[C:11](=[O:16])[NH:10][C:9]=2[C:8]2[CH:7]=[CH:6][CH:5]=[CH:4][C:3]1=2.[CH3:17][O:18][CH2:19][CH2:20]O.C1(C)C=CC(S(O)(=O)=O)=CC=1.O>C1C=CC=CC=1>[CH3:17][O:18][CH2:19][CH2:20][O:1][CH:2]1[C:14]2[NH:13][C:12](=[O:15])[C:11](=[O:16])[NH:10][C:9]=2[C:8]2[CH:7]=[CH:6][CH:5]=[CH:4][C:3]1=2

Participants

6

Reactant 4

HCID 962WaterHCID 6101p-Toluenesulfonic acidHCID 80192-MethoxyethanolHCID 190359859-Hydroxy-9H-indeno[1,2-b]pyrazine-2,3(1H,4H)-dione

Product 1

HCID 231940579-(2-Methoxyethoxy)-9H-indeno[1,2-b]pyrazine-2,3(1H, 4H)-dioneYield 60%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

A suspension of 9-hydroxy-9H-indeno[1,2-b]pyrazine-2,3(1H, 4H)-dione. 1H2O (0.50 g, 2.13 mmol) in benzene (20 ml), 2-methoxyethanol (10 ml) and p-toluensulfonic acid (20 mg) was refluxed with water separation for 20 hours. The reaction mixture was evaporated in vacuo to dryness, the residue was suspended in ethanol (10 ml) and the precipitate was filtered off and washed with ethanol and dried to give 0.48 g of the crude product, which was recrystallized from ethanol to yield 0.35 g (60%) of the title compound. M.p. >300° C. 1H-NMR (DMSO-d6, δ): 3.22 (s, 3H), 3.27-3.51 (m, 4H), 5.24 (s, 1H), 7.18 (t, 1H), 7.33 (t, 1H), 7.42 (d, 1H), 7.5 (d, 1H), 2.06 (s, 1H), 12.29 (s, 1H).

Workup

  1. customThe reaction mixture was evaporated in vacuo to dryness
  2. filtrationthe precipitate was filtered off
  3. washwashed with ethanol
  4. customdried
  5. customto give 0.48 g of the crude product, which
  6. customwas recrystallized from ethanol

Sources & evidence

ORD record
ord-8bf8ea965d464656810ab095eddd73d9
Source dataset
uspto-grants-1995_11
Patent number
US05468748

Linked notes

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