反应详情

To a stirred solution of tert-butyl 4-(5-iodopyridin-2-yl)piperazine-1-carboxylate (4.087 g, 10.5 mmol) in DMA (75 mL) at RT was added 2-ethynylpyridine, (CAS number 1945-84-2, 1.17 mL, 11.5 mmol), triethylamine (4.4 mL, 31.5 mmol), CuI (800 mg, 4.2 mmol) and Pd(PPh3)4 (1.21 g, 1.05 mmol). After stirring for 30 minutes, the DMA was removed in vacuo, and the residue diluted with EtOAc (100 mL). The dark solution was then washed with water (100 mL). The layers were separated and the aqueous phase extracted with EtOAc (3×50 mL). The combined organic extracts were then dried, (MgSO4), filtered and concentrated in vacuo. The residue was then purified by flash chromatography (silica gel, 50% EtOAc in hexanes) to give tert-butyl 4-[5-(pyridin-2-ylethynyl)pyridin-2-yl]piperazine-1-carboxylate as a brown oil (3.8 g, 10.5 mmol, 99%).

1. customthe DMA was removed in vacuo
2. additionthe residue diluted with EtOAc (100 mL)
3. washThe dark solution was then washed with water (100 mL)
4. customThe layers were separated
5. extractionthe aqueous phase extracted with EtOAc (3×50 mL)
6. dry with materialThe combined organic extracts were then dried, (MgSO4),
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe residue was then purified by flash chromatography (silica gel, 50% EtOAc in hexanes)