Dimethyl Sulfate → Methyl 4,6-dibromo-3-methoxypyridine-2-carboxylate

HRID 378788Notes

Reaction equation

HRID 378788 reaction equation
[Br:1][C:2]1[CH:7]=[C:6]([Br:8])[N:5]=[C:4]([C:9]([O:11][CH3:12])=[O:10])[C:3]=1[OH:13].[C:14]([O-])([O-])=O.[K+].[K+].S(OC)(OC)(=O)=O>CC(C)=O>[Br:1][C:2]1[CH:7]=[C:6]([Br:8])[N:5]=[C:4]([C:9]([O:11][CH3:12])=[O:10])[C:3]=1[O:13][CH3:14]

Participants

5

Reactant 3

HCID 6497Dimethyl SulfateHCID 11430Potassium CarbonateHCID 22175130Methyl 4,6-dibromo-3-hydroxypicolinate

Product 1

HCID 21696615Methyl 4,6-dibromo-3-methoxypyridine-2-carboxylate

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

To methyl 4,6-dibromo-3-hydroxypyridine-2-carboxylate 3.98 g (3.98 g, 12.81 mmol) in 40 mL of acetone was added K2CO3 (2.0 g, 14.47 mmol) and dimethyl sulfate (1.20 mL, 12.37 mmol). The reaction mixture was refluxed overnight and concentrated to dryness. The residue was dissolved in ethyl acetate and saturated sodium bicarbonate. The phases were separated and the aqueous phase was extracted with ethyl acetate (3×100 mL). The combined extracts were dried (MgSO4) and concentrated to dryness. The residue was purified by chromatography (silica gel). Elution with 15% ethyl acetate/hexane gave 0.980 g, of a white solid. 1H NMR(CDCl3): δ 3.95 (s, 3H); 3.90 (s, 3H); 7.80 (s, 1H).

Workup

  1. temperatureThe reaction mixture was refluxed overnight
  2. concentrationconcentrated to dryness
  3. dissolutionThe residue was dissolved in ethyl acetate
  4. customThe phases were separated
  5. extractionthe aqueous phase was extracted with ethyl acetate (3×100 mL)
  6. dry with materialThe combined extracts were dried (MgSO4)
  7. concentrationconcentrated to dryness
  8. customThe residue was purified by chromatography (silica gel)
  9. washElution with 15% ethyl acetate/hexane
  10. customgave 0.980 g

Sources & evidence

ORD record
ord-d990773cac07439fa8802b2c3bec45d0
Source dataset
uspto-grants-2001_10
Patent number
US06297197B1

Reaction notes

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