Reaction #465966

ord-964e8f1c76be44a193d614288924623d

Reaction equation

O=C(O)c1nc(Cl)ccc1Cl
3,6-dichloropyridine-2-carboxylic acid
CO
methanol
COC(=O)c1nc(Cl)ccc1Cl
light yellow solid
COC(=O)c1nc(Cl)ccc1Cl
Methyl 3,6-Dichloropyridine-2-carboxylate

Conditions

Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    OtherTo a 3-neck round bottom flask equipped with a reflux condenser
  2. 2
    OtherHCl(g) was bubbled in until solution
  3. 3
    ConcentrationThe solution was concentrated to dryness in vacuo
  4. 4
    workup.ADDITIONDiethyl ether was added
  5. 5
    workup.ADDITIONwas subsequently added to a flask
  6. 6
    workup.ADDITIONfilled with a 1:1 mixture of saturated sodium bicarbonate/diethyl ether
  7. 7
    workup.STIRRINGstirred for 10 min
  8. 8
    ExtractionThe aqueous phase was extracted with diethyl ether (3×300 mL)
  9. 9
    DryingThe combined extracts were dried (MgSO4)
  10. 10
    Concentrationconcentrated

Procedure

To a 3-neck round bottom flask equipped with a reflux condenser was added 3,6-dichloropyridine-2-carboxylic acid (50.0 g, 260.42 mmol) in methanol (200 mL). HCl(g) was bubbled in until solution became saturated and stirred at room temperature for 2 hr. The solution was concentrated to dryness in vacuo. Diethyl ether was added to make a slurry that was subsequently added to a flask filled with a 1:1 mixture of saturated sodium bicarbonate/diethyl ether and stirred for 10 min. The aqueous phase was extracted with diethyl ether (3×300 mL). The combined extracts were dried (MgSO4) and concentrated to give 46.6 g of a light yellow solid. 1H NMR(CDCl3): δ 4.00 (s, 3H); 7.41 (d, 1H); 7.80 (d, 1H).

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US06297197B1uspto-grants-2001_10