Sulfuric Acid → Methyl 5,6-Dichloronicotinate

HRID 1430096Notes

Reaction equation

HRID 1430096 reaction equation
S(=O)(=O)(O)O.[Cl:6][C:7]1[C:8]([Cl:16])=[N:9][CH:10]=[C:11]([CH:15]=1)[C:12]([OH:14])=[O:13].[C:17](=O)(O)[O-].[Na+]>CO>[CH3:17][O:13][C:12](=[O:14])[C:11]1[CH:15]=[C:7]([Cl:6])[C:8]([Cl:16])=[N:9][CH:10]=1

Participants

5

Reactant 3

HCID 1118Sulfuric AcidHCID 2479875,6-Dichloronicotinic acidHCID 516892Sodium Bicarbonate

Product 1

HCID 2782166Methyl 5,6-DichloronicotinateYield 97%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Conditions

Temperature
4 °C

Procedure

4.45 mL of sulfuric acid was added to 5.0 g of 5,6-dichloronicotinic acid (26 mmol) dissolved in 50 mL of methanol, and refluxed under heating and stirring for 18 hours. The mixture was cooled to 4° C. neutralized with a saturated sodium bicarbonate solution, and methanol was concentrated under reduced pressure. The aqueous layer was extracted with ethyl acetate, and the organic layer was separated to be dried over magnesium sulfate, and concentrated under reduced pressure. The residue was separated by column chromatography (eluting solvent: chloroform/methanol=20/1) to obtain 5.2 g of white solid, 5,6-dichloro-nicotinic acid methyl ester (yield 97%).

Workup

  1. temperaturerefluxed
  2. temperatureunder heating
  3. concentrationwas concentrated under reduced pressure
  4. extractionThe aqueous layer was extracted with ethyl acetate
  5. customthe organic layer was separated
  6. dry with materialto be dried over magnesium sulfate
  7. concentrationconcentrated under reduced pressure
  8. customThe residue was separated by column chromatography (eluting solvent: chloroform/methanol=20/1)

Sources & evidence

ORD record
ord-a1783a3cb4f24e6ba0a1067558cac863
Source dataset
uspto-grants-2015_01
Patent number
US08940769B2

Reaction notes

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