反应详情

温度

80 °C

21.4 g of dimethyl carbonate was added dropwise to a stirred mixture of 5.7 g of sodium hydride and 100 ml of toluene at room temperature. Then the mixture was heated to 80° C. and a solution of 16.1 g of 2-acetyl-3-methylpyrazine in 75 ml of toluene was added dropwise and the mixture was stirred at 75° C. for one hour. The mixture was cooled, 100 ml of water was added and the mixture was acidified with glacial acetic acid. The organic phase was separated, dried (Na2SO4) and stripped of volatiles. The residue was flash chromatographed on silica gel, with a 9:1 v:v mixture of methyl chloride and ethyl acetate as eluent. The second set of fractions was stripped of solvent to give methyl 3-(3-methyl-2-pyrazinyl)-3-oxopropionate (31A), as a yellow oil.

1. temperatureThe mixture was cooled
2. customThe organic phase was separated
3. dry with materialdried (Na2SO4)
4. customchromatographed on silica gel, with a 9:1 v
5. additionv mixture of methyl chloride and ethyl acetate as eluent