反应详情

温度

-78 °C

To a solution of 2-(1,1-dimethoxyethyl)-1,3-thiazole (40 g, 0.23 mol) in THF (600 ml) was added n-BuLi (100 ml, 0.25 mol) dropwise at −78° C. After stirring for 1 h at −78° C., a solution of CBr4 (300 g, 0.9 mol) in THF (300 ml) was added drop-wise. The reaction mixture was stirred for another 1 h at −78° C., and then was quenched by the addition of sat. aq. NH4Cl and was extracted with ethyl acetate (150 ml×3). The organic layers were washed with brine, dried over Na2SO4 and concentrated. The residue was purified by column (eluted by petroleum ether/EtOAc=10:1) to afforded 25 g of 5-bromo-2-(1,1-dimethoxyethyl)-1,3-thiazole as solid (43%). 1H-NMR (CDCl3 400 MHz) δ 7.81 (s, 1H, Ar—H), 3.23 (s, 6H, —OCH3), 1.72 (s, 3H, —CH3).

1. stirringThe reaction mixture was stirred for another 1 h at −78° C.
2. customwas quenched by the addition of sat. aq. NH4Cl
3. extractionwas extracted with ethyl acetate (150 ml×3)
4. washThe organic layers were washed with brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated
7. customThe residue was purified by column (eluted by petroleum ether/EtOAc=10:1)