反应详情

温度

-78 °C

2-(tert-Butyl-dimethyl-silyl)-4,5-dihydro-imidazole-1-sulfonic acid dimethylamide (5.03 g) (prepared as described by Ngochindo, J. Chem. Soc. Perkin Trans. (1990) 1:1645) was dissolved in 100 ml of dry tetrahydrofuran and cooled in a dry ice-acetone bath to -78° C.; 11.9 ml of 1.6M n-butyllithium in hexane was added to this mixture. After 1 hr at -78° C., the reaction mixture was treated dropwise with 5.0 g of 4-bromomethyl-1-methyl-2-nitro-benzene dissolved in 25 ml of dry tetrahydrofuran (THF). The mixture was stirred at -78° C. for 1 hr and then allowed to come to room temperature overnight. The mixture was treated with saturated ammonium chloride, extracted with ethyl acetate washed the combined extracts with saturated sodium chloride, dried, and evaporated to dryness. The residue was purified by flash chromatography on silica gel and eluted with ethyl acetate:hexane (1:4 ) to give 2.39 g of 2-(tert-butyl-dimethyl-silyl)-5-(4-methyl-3-nitro-benzyl)-imidazole-1-sulfonic acid dimethylamide as a yellow oil. ##STR126##

1. waitto come to room temperature overnight
2. extractionextracted with ethyl acetate
3. washwashed the combined extracts with saturated sodium chloride
4. customdried
5. customevaporated to dryness
6. customThe residue was purified by flash chromatography on silica gel
7. washeluted with ethyl acetate:hexane (1:4 )