反应详情

温度

100 °C

A solution of tert-butyl 4-methyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenylcarbamate (from step 2) (1.0 eq.) and 3-bromopicolino-nitrile (1.0 eq.) in toluene (0.44 M) was mixed with tetrakis(triphenyl-phosphine)palladium (5 mol %) and 2N aqueous potassium carbonate solution (2.0 eq.). The reaction was heated to 100° C. and stirred overnight. After cooling to ambient temperature, the reaction content was diluted with 2% methanol in dichloromethane and water. The two phases were separated, and the aqueous layer was extracted twice with 2% methanol in dichloromethane. The combined organic layers were washed with brine, dried over anhydrous MgSO4, and concentrated en vacuo. The crude product was purified by flash chromatography on a COMBIFLASH® system (ISCO) using 0-5% methanol in dichloromethane to give a semipure solid, which was then swirled in hot ethyl acetate, filtered, and dried to give a pure solid. 1H NMR (acetone d-6): δ 9.02 (d, 1H), 8.89 (d, 1H), 8.25 (s, 1H), 7.80-7.84 (dd, 1H), 7.52 (d, 1H), 7.40 (d, 1H), 6.5 (br, 2H), 2.48 (s, 3H). LRMS [M+H]=210.2

1. temperatureAfter cooling to ambient temperature
2. customThe two phases were separated
3. extractionthe aqueous layer was extracted twice with 2% methanol in dichloromethane
4. washThe combined organic layers were washed with brine
5. dry with materialdried over anhydrous MgSO4
6. concentrationconcentrated en vacuo
7. customThe crude product was purified by flash chromatography on a COMBIFLASH® system (ISCO)
8. customto give a semipure solid, which
9. filtrationfiltered
10. customdried
11. customto give a pure solid