Phosphorus oxychloride → Methyl 5-chloropyrazine-2-carboxylate

HRID 340088Notes

Reaction equation

HRID 340088 reaction equation
[CH3:1][O:2][C:3]([C:5]1[CH:10]=[N:9][C:8](O)=[CH:7][N:6]=1)=[O:4].O=P(Cl)(Cl)[Cl:14]>>[CH3:1][O:2][C:3]([C:5]1[CH:10]=[N:9][C:8]([Cl:14])=[CH:7][N:6]=1)=[O:4]

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 178498852HCID 178498852, compound

Product 1

HCID 406081Methyl 5-chloropyrazine-2-carboxylateYield 55.1%

Procedure

A mixture of 5-hydroxy-pyrazine-2-carboxylic acid methyl ester (Preparation 40, 50 g, 324 mmol) and POCl3 (500 mL, 5.36 mol) was heated under reflux for 1.5 hours and then poured onto ice. The resulting mixture was extracted with ether (4×500 mL). The organic layers were concentrated in vacuo, and the residue was recrystallised from toluene to give the title compound (30.8 g) in a 55% yield.

Workup

  1. temperaturewas heated
  2. temperatureunder reflux for 1.5 hours
  3. additionpoured onto ice
  4. extractionThe resulting mixture was extracted with ether (4×500 mL)
  5. concentrationThe organic layers were concentrated in vacuo
  6. customthe residue was recrystallised from toluene

Sources & evidence

ORD record
ord-c1d6df4458084bd5a9aa6c99389f3a42
Source dataset
uspto-grants-2014_11
Patent number
US08895544B2

Reaction notes

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