反应详情

To a stirring solution of 1.3 g (7.33 mmol) of methyl 2-cyano-6-methylisonicotinate in 25 mL of MeOH and 5 mL of THF at 0° C. was added 823 mg (21.7 mmol) of NaBH4. After 2 h the ice bath was removed and stirring was continued with warming to r.t. and after a further 15 min. 1.06 g of NaBH4 was added. After another 15 min., the solution was concentrated, and EtOAc was added. The pH was adjusted to 7 with 1N HCl, and the layers were separated. The aqueous layer was extracted with EtOAc (2×), and the combined extracts were washed with brine (50 mL), dried over Na2SO4, filtered, and concentrated. Purification by flash silica gel chromatography (2-3) % MeOH/CHCl3 provided 440 mg of 4-(hydroxymethyl)-6-methylpicolinonitrile in 40% yield as a colorless solid.

1. customAfter 2 h the ice bath was removed
2. addition1.06 g of NaBH4 was added
3. concentrationthe solution was concentrated
4. additionEtOAc was added
5. customthe layers were separated
6. extractionThe aqueous layer was extracted with EtOAc (2×)
7. washthe combined extracts were washed with brine (50 mL)
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated
11. customPurification by flash silica gel chromatography (2-3) % MeOH/CHCl3