Stannous chloride dihydrate → 7-fluoro-6-methyl-3,4-dihydroquinoxalin-2(1H)-one

HRID 1600746Notes

Reaction equation

HRID 1600746 reaction equation
[Na+].[F:2][C:3]1[C:8]([CH3:9])=[CH:7][C:6]([NH:10][CH2:11][C:12]([O-])=[O:13])=[C:5]([N+:15]([O-])=O)[CH:4]=1.O.O.[Sn](Cl)Cl>C(O)C>[F:2][C:3]1[CH:4]=[C:5]2[C:6]([NH:10][CH2:11][C:12](=[O:13])[NH:15]2)=[CH:7][C:8]=1[CH3:9]

Participants

4

Reactant 2

HCID 61436Stannous chloride dihydrateHCID 21189988HCID 21189988, compound

Product 1

HCID 104197697-fluoro-6-methyl-3,4-dihydroquinoxalin-2(1H)-oneYield 32.4%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of N-(4-fluoro-5-methyl-2-nitrophenyl)glycine sodium salt (0.125 g, 0.548 mmol) and tin (II) chloride dihydrate (0.370 g, 1.64 mmol, Aldrich, used as received) in ethanol (3.0 mL) was refluxed for 30 min. It was then cooled to room temperature and the solvent was removed under vacuum. The residue was diluted with water (4.0 mL) and basified with saturated NaHCO3 to pH~8. The resulting suspension was extracted with ethyl acetate (30 mL). The extract was dried over Na2SO4 and evaporated to yield 0.032 g of the title compound as a yellow powder, which was used for the next reaction; 1H NMR (DMSO-d6): 2.024 (s, 3H), 3.607 (s, 2H), 5.751 (s, 1H), 6.453 (d, 1H, J=9.9 Hz), 6.456 (d, 1H, J=8.1 Hz), 10.162 (s, 1H).

Workup

  1. temperaturewas refluxed for 30 min
  2. customthe solvent was removed under vacuum
  3. additionThe residue was diluted with water (4.0 mL)
  4. extractionThe resulting suspension was extracted with ethyl acetate (30 mL)
  5. dry with materialThe extract was dried over Na2SO4
  6. customevaporated

Sources & evidence

ORD record
ord-8a7a254a3be543ea9d95fa72f364eb7f
Source dataset
uspto-grants-1999_11
Patent number
US05977107

Reaction notes

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