反应详情

To a suspension of 2-methylnicotinamide from step 1 (11.1 g, 0.081 mol) in triethylamine (24.8 g, 0.243 mol) and 400 mL of methylene chloride was added trifluoroacetic anhydride (21.0 g, 0.100 mol) rapidly at 0° C. The reaction was complete after a few minutes at this temperature. Water was added and the aqueous layer was extracted with methylene chloride. The combined organic layers were washed with water, brine and dried over magnesium sulfate. After filtration, the filtrate was concentrated and the residue was purified by chromatography on silica gel (ethyl acetate/hexane, 1:1) to give 7.2 g of 3-cyano-2methylpyridine as a pale yellow solid (75%): mp(DSC) 56°-58° C.

1. waitThe reaction was complete after a few minutes at this temperature
2. extractionthe aqueous layer was extracted with methylene chloride
3. washThe combined organic layers were washed with water, brine
4. dry with materialdried over magnesium sulfate
5. filtrationAfter filtration
6. concentrationthe filtrate was concentrated
7. customthe residue was purified by chromatography on silica gel (ethyl acetate/hexane, 1:1)