反应详情

tert-Butyl 7,8-di hydroxy-2,3-d i-p-tolyl-7,8-dihydropyrido[2,3-b]pyrazine-5(6H)-carboxylate (step 2) (1.28 g, 2.86 mmol) was dissolved in tetrahydrofuran (50 ml). 1,1′-Thiocarbonyl diimidazole (1.019 g, 5.72 mmol) was added and the solution heated at reflux for 3 h. The reaction mixture was cooled to room temperature and evaporated to dryness. Water and DCM (300 ml) were added. The organic layer was separated and evaporated to dryness. Ethyl acetate (5 ml) was added to the dark residue and the resulting solid filtered off. The solid was washed twice with EtOAc (5 ml) to afford the titled compound;

1. temperaturethe solution heated
2. temperatureat reflux for 3 h
3. customevaporated to dryness
4. additionWater and DCM (300 ml) were added
5. customThe organic layer was separated
6. customevaporated to dryness
7. additionEthyl acetate (5 ml) was added to the dark residue
8. filtrationthe resulting solid filtered off
9. washThe solid was washed twice with EtOAc (5 ml)