Synthesis
Synthesis of 2,6-dimethoxypyrazine (V): a mixture of 2,6-dichloropyrazine (3.9 g, 26 mmol) with freshly prepared sodium methanol (62 mmol) in anhydrous methanol (50 ml) was heated to reflux overnight. After completion of the reaction, the solvent was removed under reduced pressure. The residue was diluted to 100 ml with dichloromethane (CH2Cl2), washed sequentially with water and saturated saline, then dried over anhydrous magnesium sulfate (MgSO4) and filtered. The filtrate was concentrated by evaporation under reduced pressure to give pure 2,6-dimethoxypyrazine (V) (3.6 g, 98% yield) as colorless crystals. Its 1H NMR (CDCl3) data were as follows: δ 3.94 (s, 6H); 7.76 (s, 2H).
References
[1] Tetrahedron, 2009, vol. 65, # 43, p. 8891 - 8895
[2] Patent: WO2008/70908, 2008, A1. Location in patent: Page/Page column 76-77
[3] Asian Journal of Chemistry, 2013, vol. 25, # 9, p. 4979 - 4982
[4] Journal of Heterocyclic Chemistry, 2016, vol. 53, # 5, p. 1386 - 1394
[5] Journal of the Chemical Society, 1965, p. 6681,6686
