Methanol → Methyl 3-methylpyrazine-2-carboxylate

A solution of 3-methylpyrazine-2-carboxylic acid (10 g, 72.4 mmol) in 80 mL methanol and sulfuric acid, 95% (5 ml, 90 mmol) was heated to 60° C. for 4 h. The solution was concentrated to remove MeOH, the residue was dissolved in 50 mL of water and neutralized with 10% aq Na2CO3 solution to pH 12. The resulting solution was extracted with ethyl acetate. The combined organics were dried and concentrated to give crude methyl 3-methylpyrazine-2-carboxylate (9.1 g, 83% yield) which was used for next step without further purification.

1. concentrationThe solution was concentrated
2. customto remove MeOH
3. dissolutionthe residue was dissolved in 50 mL of water and neutralized with 10% aq Na2CO3 solution to pH 12
4. extractionThe resulting solution was extracted with ethyl acetate
5. customThe combined organics were dried
6. concentrationconcentrated

ORD-Eintrag

ord-133c193d616d4564a7551541c0a115c3

Quelldatensatz

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09309263B2