反应详情

(2-chloro-4-iodo-pyridin-3-yl)-carbamic acid tert-butyl ester a (4.20 g, 11.8 mmol), phenyl boronic acid (1.90 g, 15.6 mmol), potassium carbonate (2.42 g, 17.5 mmol) and tetrakistriphenylphosphine palladium(0) (0.68 g, 0.59 mmol) were weighed into a 20 ml microwave vial. The vial was evacuated, then purged with nitrogen gas 3 times. 16.7 ml dry DMF was added, then 3.3 ml of water, which had been degassed by bubbling nitrogen through it overnight. The vial was then capped and microwaved at 130° C. for 40 minutes. The resulting solution was poured into 250 ml water and extracted with EtOAc (3×50 ml). The combined organics were dried with MgSO4, filtered and concentrated. The resulting oil was adsorbed onto silica gel and purified by flash chromatography (150 g SiO2, 0% to 40% EtOAc in hexanes) to give 2-chloro-3-amino-4-phenyl pyridine b (0.84 g, 4.1 mmol, 35%) and the Boc-protected 2-chloro-3-amino-4-phenyl pyridine c (1.74 g, 5.7 mmol, 48%) as yellow and white solids, respectively.

1. customThe vial was evacuated
2. custompurged with nitrogen gas 3 times
3. addition16.7 ml dry DMF was added
4. custom3.3 ml of water, which had been degassed
5. customby bubbling nitrogen through it overnight
6. customThe vial was then capped
7. custommicrowaved at 130° C. for 40 minutes
8. additionThe resulting solution was poured into 250 ml water
9. extractionextracted with EtOAc (3×50 ml)
10. dry with materialThe combined organics were dried with MgSO4
11. filtrationfiltered
12. concentrationconcentrated
13. custompurified by flash chromatography (150 g SiO2, 0% to 40% EtOAc in hexanes)