反应详情

A solution of 2-ethyl butyraldehyde (6 g, 60 mmol) in CH2Cl2 (75 mL) was stirred vigorously with a solution of sodium bisulfite (9.4 g, 90 mmol) in water (35 mL). The thick precipitate which had formed was collected by filtration and washed with CH2Cl2 and dried in vacuo. The bisulfite adduct (10 g, 49 mmol) was dissolved in water (60 mL) and to the solution was added sodium cyanide (3.6 g, 73 mmol). The resulting solution was stirred at ambient temperature for 48 h. The mixture was extracted with ether (2×100 mL) and the combined extracts were dried (MgSO4), filtered, and the solvent was removed in vacuo. The residue was purified by flash silica gel column chromatography using a gradient elution of 10%, 12.5%, 15% EtOAc in hexanes. The product-containing fractions were combined to give 1-cyano-2-ethylbutanol as a liquid after removal of the solvents in vacuo (5.0 g; TLC Rf=0.4 (9:1 hexanes:EtOAc); 400 MHz 1H NMR, CDCl3, 4.51 ppm (dd, 1H), 2.45 ppm (d, 1H), 1.4-1.7 ppm (overlapping m, 5H), 0.98 ppm (overlapping t, 6H)).

1. customThe thick precipitate which had formed
2. filtrationwas collected by filtration
3. washwashed with CH2Cl2
4. customdried in vacuo
5. extractionThe mixture was extracted with ether (2×100 mL)
6. dry with materialthe combined extracts were dried (MgSO4)
7. filtrationfiltered
8. customthe solvent was removed in vacuo
9. customThe residue was purified by flash silica gel column chromatography
10. washa gradient elution of 10%, 12.5%, 15% EtOAc in hexanes