Ethanol → HCID 23512429, compound

HRID 350454Notes

Reaction equation

HRID 350454 reaction equation
[F:1][C:2]1[C:7]([F:8])=[C:6]([N+:9]([O-])=O)[CH:5]=[CH:4][C:3]=1[CH2:12][C:13]([O:15]CC)=[O:14].Cl[Sn]Cl.[CH3:21][CH2:22]O>>[CH2:21]([CH:12]([C:3]1[CH:4]=[CH:5][C:6]([NH2:9])=[C:7]([F:8])[C:2]=1[F:1])[C:13]([OH:15])=[O:14])[CH3:22]

Participants

4

Reactant 3

HCID 702EthanolHCID 24479Stannous ChlorideHCID 58785152HCID 58785152, compound

Product 1

HCID 23512429HCID 23512429, compoundYield 38%

Procedure

To a stirred solution of ethyl 2,3-difluoro-4-nitrophenylacetate (5.85 g, 23.9 mol) in EtOH (100 mL), was added SnCl2 (16.1 g, 71.6 mmol) at rt. The stirring was continued for 18 hours at reflux. After removal of the solvent, the residue was dissolved in CHCl3 (100 mL) and poured into ice water-4M NaOH (40 mL of 4M NaOH in 300 mL of ice-water), extracted with CHCl3 (100 mL×2), dried over anhydrous MgSO4, and concentrated under a reduced pressure. The residue was chromatographed on silica gel (middle pressure chromatography system YAMAZEN YFLC-5404, linear gradient of hexane-EtOAc from 9:1 to 7:3, φ50 mg×500 mg, 15 ml/min) to give ethyl 4-amino-2,3-difluorophenylacetic acid (1.94 g, 38%) as a colorless oil. 1H-NMR (CDCl3) δ 1.25 (t, J=7.3 Hz, 3 H), 3.55 (d, J=1.0 Hz, 2 H), 3.78 (br s, 2 H), 4.15 (dd, J=7.2 Hz, 14.2 Hz, 2 H), 6.49 (dt, J=1.8, 8.2 Hz, 1 H), 6.78 (m, 1 H); MS (FAB) m/z 216 (M++1).

Workup

  1. temperatureat reflux
  2. customAfter removal of the solvent
  3. dissolutionthe residue was dissolved in CHCl3 (100 mL)
  4. additionpoured into ice water-4M NaOH (40 mL of 4M NaOH in 300 mL of ice-water)
  5. extractionextracted with CHCl3 (100 mL×2)
  6. dry with materialdried over anhydrous MgSO4
  7. concentrationconcentrated under a reduced pressure
  8. customThe residue was chromatographed on silica gel (middle pressure chromatography system YAMAZEN YFLC-5404, linear gradient of hexane-EtOAc from 9:1 to 7:3, φ50 mg×500 mg, 15 ml/min)

Sources & evidence

ORD record
ord-50d426bc5f34447d9f49668690afdfb0
Source dataset
uspto-grants-2007_02
Patent number
US07179819B2

Reaction notes

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