Hydroxyamine hydrochloride → (NE)-N-[(4-fluoro-1-hydroxy-3,3-dimethyl-2,1-benzoxaborol-6-yl)methylidene]hydroxylamine

HRID 1037139Notes

Reaction equation

HRID 1037139 reaction equation
[F:1][C:2]1[C:10]2[C:9]([CH3:12])([CH3:11])[O:8][B:7]([OH:13])[C:6]=2[CH:5]=[C:4]([CH:14]=O)[CH:3]=1.[NH2:16][OH:17].Cl.CC([O-])=O.[Na+]>C1COCC1.O>[F:1][C:2]1[C:10]2[C:9]([CH3:12])([CH3:11])[O:8][B:7]([OH:13])[C:6]=2[CH:5]=[C:4](/[CH:14]=[N:16]/[OH:17])[CH:3]=1

Participants

6

Reactant 3

HCID 443297Hydroxyamine hydrochlorideHCID 517045Sodium AcetateHCID 866855024-Fluoro-1-hydroxy-3,3-dimethyl-1,3-dihydrobenzo[c][1,2]oxaborole-6-carbaldehyde

Product 1

HCID 89573609(NE)-N-[(4-fluoro-1-hydroxy-3,3-dimethyl-2,1-benzoxaborol-6-yl)methylidene]hydroxylamineYield 95.8%

Reagents, catalysts & solvents 2

HCID 962WaterSolvent2×HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 4-fluoro-1-hydroxy-3,3-dimethyl-1,3-dihydrobenzo[c][1,2]oxaborole-6-carbaldehyde (1.86 g, 8.94 mmol) and NH2OH.HCl (0.69 g, 9.84 mmol) in THF (16 mL) and H2O (4 mL) at rt was added NaOAc (0.92 g, 11.18 mmol). The reaction mixture was stirred for 3 h and diluted with H2O. The mixture was extracted with EA and the organic layer was separated. The organic solution was washed with brine, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by column chromatography over silica gel eluted with PE-EA (5:1 to 2:1) to give (E)-4-fluoro-1-hydroxy-3,3-dimethyl-1,3-dihydrobenzo[c][1,2]oxaborole-6-carbaldehyde oxime (1.8 g, 95.8% yield) as a light yellow solid. 1H NMR (500 MHz, DMSO-d6) δ 11.38 (s, 1H), 9.34 (s, 1H), 8.19 (s, 1H), 7.74 (s, 1H), 7.46 (dd, J=1.2 Hz, J=11.2 Hz, 1H), 1.524 (s, 6H) ppm.

Workup

  1. extractionThe mixture was extracted with EA
  2. customthe organic layer was separated
  3. washThe organic solution was washed with brine
  4. dry with materialdried over Na2SO4
  5. filtrationfiltered
  6. concentrationconcentrated under reduced pressure
  7. customThe residue was purified by column chromatography over silica gel
  8. washeluted with PE-EA (5:1 to 2:1)

Sources & evidence

ORD record
ord-a3f59dd8b0644f6db1ce84d60db103bc
Source dataset
uspto-grants-2013_10
Patent number
US08546357B2

Reaction notes

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