反应详情

Dissolve 2,3-dichloropyrazine (2.42 g, 2.03 mmol) and 3,4-dichlorobenzene boronic acid (0.406 g, 2.13 mmol) in toluene (6 mL). Add a solution of potassium fluoride (0.36 g; 6.2 mmol) in deionized water (5 mL). Add tetrakis triphenylphosphine (0.124 gm; 0.11 mmol). Reflux the reaction for 17 hr.s, cool to ambient temperature, and add EtOAc (10 mL) and water (10 mL). Separate the organic layer, re-extract the aqueous layer with EtOAc (2×40 mL), and combine the organic layers. Wash the organic solution with saturated aq NaHCO3 and brine (2×), dry over MgSO4, filter and concentrate. Purify via chromatography on silica gel eluting 0-40% ethyl acetate/hexanes to give the title preparation (0.124 g, 23% yield). MS (ES) m/z: 274, 276 (M)+.

1. temperatureReflux
2. customthe reaction for 17 hr
3. customSeparate the organic layer
4. extractionre-extract the aqueous layer with EtOAc (2×40 mL)
5. washWash the organic solution with saturated aq NaHCO3 and brine (2×)
6. dry with materialdry over MgSO4
7. filtrationfilter
8. concentrationconcentrate
9. customPurify via chromatography on silica gel eluting 0-40% ethyl acetate/hexanes
10. customto give the title
11. custompreparation (0.124 g, 23% yield)