Ammonia → 2-Amino-5-chloro-6-methylpyrazine
Reaktionsgleichung
Cl[C:2]1[CH:3]=[N:4][C:5]([Cl:9])=[C:6]([CH3:8])[N:7]=1.[NH3:10]>>[NH2:10][C:2]1[CH:3]=[N:4][C:5]([Cl:9])=[C:6]([CH3:8])[N:7]=1Komponenten
3
Reaktionsbedingungen
- Temperatur
- 135 °C
Versuchsvorschrift
A mixture of 3,6-dichloro-5-methylpyrazine (5 g, 30.7 mmol) in ethanolic ammonia solution (50 ml) was heated for 8 hours in a high-pressure cell at 135° C. The solvent was then removed by evaporation and the residue dissolved in chloroform (40 ml). The organic solution was washed with water (2×25 ml) dried (MgSO4) and the volatiles removed by evaporation. The crude solid was semi-purified by column chromatography on silica gel eluting with dichloromethane/methanol (95:5) to the title compound (1.3 g, 31%) as a 10:17 mixture with its regioisomer. NMR: 2.06 (s, 3H), 2.18 (s, 3H), 6.2 (br s, 4H), 6.74 (s, 1H), 7.26 (s, 1H); m/z: 143 [MH]+.