反应详情

Oxalyl chloride (0.288 ml, 3.32 mmol) was added to a suspension of 1-methyl-1H-pyrazole-5-carboxylic acid (0.279 g, 2.21 mmol) in dichloromethane (5 ml) followed by 1 drop of dimethylformamide. The mixture was stirred at room temperature for 4 hours before concentrating in vacuo and azeotroping with dichloromethane. The residue was taken up in pyridine (1 ml) and added to a solution of 3-chloro-pyrazine-2,6-diamine (Preparation 1) (0.16 g, 1.11 mmol) and the mixture heated at 60° C. for 3 hours before cooling to room temperature and concentrating in vacuo. The residue was purified by silica gel column chromatography, eluting with ethylacetate:heptane 1:1, to afford the product as a pale solid (100 mg).

1. concentrationbefore concentrating in vacuo
2. customazeotroping with dichloromethane
3. temperaturethe mixture heated at 60° C. for 3 hours
4. temperaturebefore cooling to room temperature
5. concentrationconcentrating in vacuo
6. customThe residue was purified by silica gel column chromatography
7. washeluting with ethylacetate:heptane 1:1