反应详情

温度

-79 °C

A solution of 1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-pyrazole (Heterocycles (1992), 34(2), 303-14)(0.80 g, 4.03 mmol) in 50 mL of THF/ether (3/2) was cooled to −78° C. and treated with 2.5M solution of n-BuLi (1.8 mL, 4.43 mmol) dropwise under N2 atmosphere. The resulting mixture was stirred for 30 min. [Methyl(trityl)amino]acetaldehyde (1.27 g, 4.04 mmol) in 5 mL of the THF/ether solution was added to reaction mixture and stirred for 1 h at −79° C. and warmed up to room temperature. The reaction was quenched by adding NH4Cl (sat. aq.) and water dropwise and the resulting suspension was extrcted into EtOAc (2×100 mL). The organic phase was washed with water (100 mL) and brine (50 mL), dried over Na2SO4, filtered and concentrated in vacuo. The residue was chromatographed on a Flash 40M silica gel (90 g, 32-63 μm) cartridge, eluting with 20% EtOAc in n-heptane, and those fractions with Rf=0.3 by TLC(EtOAc/hexane, 3/7) were combined and concentrated in vacuo to give 0.7 g of the product as a white solid.

1. additionwas added to reaction mixture
2. temperaturewarmed up to room temperature
3. customThe reaction was quenched
4. additionby adding NH4Cl (sat. aq.) and water dropwise
5. washThe organic phase was washed with water (100 mL) and brine (50 mL)
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe residue was chromatographed on a Flash 40M silica gel (90 g, 32-63 μm) cartridge
10. washeluting with 20% EtOAc in n-heptane
11. concentrationconcentrated in vacuo