反应详情

温度

90 °C

To a suspension of 5-Bromo-pyridine-2,3-diol (10.0 g, 52.63 mmol, commercially available, CAS 34206-49-0) in NMP (100 mL) was added K2CO3 (21.97 g, 158 mmol) and dibromo methane (10.97 g, 63.16 mmol). The reaction mixture was heated to 90° C. for 16 h. EtOAc was added and the salts were filtered off. Water was added, the phases were separated and the aq layer was extracted with more ethyl acetate. The combined organic layers was dried over anhydrous Na2SO4 and concentrated under vacuo to get the crude compound. The crude compound was purified by silica gel chromatography (eluent 5% ethyl acetate in petrol ether). Yield of 6-Bromo-[1,3]dioxolo[4,5-b]pyridine 2.2 g (21%) pure by 1H NMR (400 MHz, DMSO) δ 7.71 (d, 1H, J=2 Hz), 7.55 (d, 1H, J=2 Hz), 6.20 (s, 2H). Mp 69-71 C.

1. filtrationthe salts were filtered off
2. additionWater was added
3. customthe phases were separated
4. extractionthe aq layer was extracted with more ethyl acetate
5. dry with materialThe combined organic layers was dried over anhydrous Na2SO4
6. concentrationconcentrated under vacuo