反应详情

Cool a solution of (1,3,5-triethyl-1H-pyrazol-4-yl)-acetic acid ethyl ester (0.92 g, 3.86 mmol) in tetrahydrofuran (50 mL) to −78° C. and add diisobutylaluminum hydride (16.2 mL, 16.2 mmol, 1 M in toluene) dropwise. Stir the resulting mixture for 5 hr. at −78° C. Quench the reaction mixture with saturated aqueous potassium sodium tartrate solution (30 mL) and ethyl acetate (100 mL) and stir at room temperature for 16 hr. Separate the organic layer; dry (sodium sulfate), filter and concentrate to give the title preparation as an oil (0.65 g, 87%). 1H-NMR (400 MHz, CDCl3) δ 9.57 (t, 1H), 4.01 (q, 2H), 3.38 (d, 2H), 2.57 (q, 4H), 1.39 (t, 3H), 1.20 (t, 3H), 1.15 (t, 3H).

1. customat −78° C
2. customQuench the reaction mixture with saturated aqueous potassium sodium tartrate solution (30 mL) and ethyl acetate (100 mL)
3. stirringstir at room temperature for 16 hr
4. customSeparate the organic layer
5. dry with materialdry (sodium sulfate)
6. filtrationfilter
7. concentrationconcentrate
8. customto give the title