Diisobutylaluminumhydride → 3-Methoxypyrazine-2-carbaldehyde

To an cooled solution (−78° C. internal temp) of 1 g of methyl 3-methoxypyrazine-2-carboxylate in 50 mL of toluene was added 6 mL of 1 M diisobutyl aluminum hydride in toluene. After stirring 10 min the reaction was quenched with 5 mL of methanol and concentrated under reduced pressure. To a stirred solution of the residue in 100 mL of dichloromethane was added 10 mL of water, then 10 g of MgSO4. The mixture was filtered and 1.5 g of activated MnO2 was added. The mixture was heated to reflux under nitrogen for 5 h, then cooled and filtered. Concentration under reduced pressure gave the product as an odiferous solid: MS (m+1)=139.1; 1H NMR (400 MHz, CDCl3) 10.25 (s, 1H), 8.4 (m, 2H), 4.15 (s, 3H).

1. customwas quenched with 5 mL of methanol
2. concentrationconcentrated under reduced pressure
3. additionTo a stirred solution of the residue in 100 mL of dichloromethane was added 10 mL of water
4. filtrationThe mixture was filtered
5. addition1.5 g of activated MnO2 was added
6. temperatureThe mixture was heated
7. temperatureto reflux under nitrogen for 5 h
8. temperaturecooled
9. filtrationfiltered
10. concentrationConcentration under reduced pressure

ORD record

ord-de485543dc974192b6a527eb15dc4bf8

Source dataset

uspto-grants-2010_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07855201B2