Ethanol → Ethyl 5-methylpyrazine-2-carboxylate

HRID 860766Notes

Reaction equation

[CH3:1][C:2]1[N:3]=[CH:4][C:5]([C:8]([OH:10])=[O:9])=[N:6][CH:7]=1.[CH2:11](O)[CH3:12]>S(=O)(=O)(O)O.C(=O)(O)[O-].[Na+]>[CH3:1][C:2]1[N:3]=[CH:4][C:5]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[N:6][CH:7]=1

Participants

Conditions

Temperature: 78 °C

Procedure

The reaction is carried out, under nitrogen, in a 1 L×4 neck flask equipped with a mechanical stirrer, water condenser (with gas inlet), and a thermocouple. The reactor is charged with 5-methylpyrazinecarboxylic acid (100 g), ethanol (300 g) and sulfuric acid (2 g). The contents are refluxed for eight hours at 78° C. The reaction mixture is cooled to ambient temperature and sodium bicarbonate (4 g) is added. About 75% of the solvent is removed under reduced pressure and the resulting suspension is allowed to stand overnight. The solids are filtered and washed with cold methanol (2×80 g). Drying under oven (25 inches of Hg) yielded 101.25 g (84%) of 5-methyl-2-pyrazinecarboxylic acid, ethyl ester.

Workup

customequipped with a mechanical stirrer, water condenser (with gas inlet)
temperatureThe reaction mixture is cooled to ambient temperature
customAbout 75% of the solvent is removed under reduced pressure
filtrationThe solids are filtered
washwashed with cold methanol (2×80 g)
customDrying under oven (25 inches of Hg)

Sources & evidence

ORD record: ord-4293caa8db74451984059ebef29e90f5
Source dataset: uspto-grants-2006_12
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07153965B2

Reaction notes

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