反应详情

To a stirred solution of ethyl 2-(2-pyridyl)-2-oxoacetate (1.0 g, 5.6 mmol) in 10 mL of THF at −78° C. under nitrogen atmosphere was added in 0.92M cyclopropyl magnesium bromide in THF solution (6.7 mL, 7.3 mmol). The reaction was then allowed to equilibrate to 0° C. and stir for 1 h. The reaction was quenched with saturated NH4Cl solution and partitioned between EtOAc and water. The EtOAc layer was separated, dried over anhydrous Na2SO4, and filtered. The filtrate solvent was removed under reduced pressure and the residue was purified by flash silica gel chromatography using 1% methanol in dichloromethane as an eluent. After concentration of desired fractions in vacuo ethyl 2-cyclopropyl-2-(2-pyridyl)hydroxyacetate was obtained as a yellow oil (0.9 g; 1H NMR, 400 MHz, CDCl3, 8.52 ppm (d, 1H), 7.76 ppm (m, 2H), 7.25 ppm (m, 1H), 5.18 ppm (s, 1H), 4.23 ppm (q, 2H), 1.8 ppm (m, 1H), 1.24 ppm (t, 3H), 0.72 ppm (m, 1H), 0.47 ppm (m, 2H), 0.37 ppm (m, 1H)).

1. customto equilibrate to 0° C.
2. customThe reaction was quenched with saturated NH4Cl solution
3. custompartitioned between EtOAc and water
4. customThe EtOAc layer was separated
5. dry with materialdried over anhydrous Na2SO4
6. filtrationfiltered
7. customThe filtrate solvent was removed under reduced pressure
8. customthe residue was purified by flash silica gel chromatography