O-tert-butylhydroxylamine hydrochloride → (E)-2-(3-bromo-alpha-t-butoxyimino-4-fluorobenzyl)-3-hydroxypyridine

HRID 442735Notes

Reaction equation

HRID 442735 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([CH:14]=[CH:15][C:16]=1[F:17])[C:5]([C:7]1[C:12]([OH:13])=[CH:11][CH:10]=[CH:9][N:8]=1)=O.Cl.[C:19]([O:23][NH2:24])([CH3:22])([CH3:21])[CH3:20]>C(O)(=O)C>[Br:1][C:2]1[CH:3]=[C:4]([CH:14]=[CH:15][C:16]=1[F:17])/[C:5](/[C:7]1[C:12]([OH:13])=[CH:11][CH:10]=[CH:9][N:8]=1)=[N:24]\[O:23][C:19]([CH3:22])([CH3:21])[CH3:20].[Br:1][C:2]1[CH:3]=[C:4]([CH:14]=[CH:15][C:16]=1[F:17])/[C:5](/[C:7]1[C:12]([OH:13])=[CH:11][CH:10]=[CH:9][N:8]=1)=[N:24]/[O:23][C:19]([CH3:22])([CH3:21])[CH3:20]

Participants

5

Reactant 2

HCID 2777906O-tert-butylhydroxylamine hydrochlorideHCID 539533172-(3-Bromo-4-fluorobenzoyl)-3-hydroxypyridine

Product 2

HCID 135494341(E)-2-(3-bromo-alpha-t-butoxyimino-4-fluorobenzyl)-3-hydroxypyridineHCID 136340705(Z)-2-(3-bromo-alpha-t-butoxyimino-4-fluorobenzyl)-3-hydroxypyridine

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Conditions

Temperature
90 °C

Procedure

A mixture of 2-(3-bromo-4-fluorobenzoyl)-3-hydroxypyridine (2.96 g), O-t-butyl hydroxylamine hydrochloride (1.88 g) and acetic acid (50 mL) was stirred at 90° C. for 14 hours. The reaction mixture was concentrated in vacuo, which was subjected to addition with ethyl acetate and water. The ethyl acetate solution was washed with aqueous NaHCO3 and a saturated aqueous saline solution, successively, which was dried (magnesium sulfate), followed by distilling off the solvent under reduced pressure. The residue was subjected to purification by means of a silica gel column (ethyl acetate--hexane) to afford (E)-2-(3-bromo-α-t-butoxyimino-4-fluorobenzyl)-3-hydroxypyridine (1.10 g) and (Z)-2-(3-bromo-α-t-butoxyimino-4-fluorobenzyl)-3-hydroxypyridine (1.97 g) (compounds 17 and 16).

Workup

  1. concentrationThe reaction mixture was concentrated in vacuo, which
  2. additionwas subjected to addition with ethyl acetate and water
  3. washThe ethyl acetate solution was washed with aqueous NaHCO3
  4. dry with materiala saturated aqueous saline solution, successively, which was dried (magnesium sulfate)
  5. distillationby distilling off the solvent under reduced pressure
  6. customThe residue was subjected to purification by means of a silica gel column (ethyl acetate--hexane)

Sources & evidence

ORD record
ord-060eb891c1b04e35bbda8a1fb4ae6123
Source dataset
uspto-grants-1999_04
Patent number
US05891895

Reaction notes

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