反应详情

2.5 g (13 mmol) 2,6-dimethoxy-4-chloro-pyridine and 6.21 g (65 mmol) piperazine were heated at reflux in 22 ml anhydrous pyridine for 20 hours. After cooling (precipitation was detected) 50 ml of toluene was added and the suspension was filtered. The filtrate was concentrated under reduced pressure, piperazine and pyridine were azeotropically removed by repeated evaporation with toluene (five times). The residue was triturated with diethylether/petrolether (1:1) and dried in vacuo. The product was obtained as yellow solid and used directly in the next step.

1. additionwas added
2. filtrationthe suspension was filtered
3. concentrationThe filtrate was concentrated under reduced pressure, piperazine and pyridine
4. customwere azeotropically removed
5. customevaporation with toluene (five times)
6. customThe residue was triturated with diethylether/petrolether (1:1)
7. customdried in vacuo
8. customThe product was obtained as yellow solid