反应详情
EQUATION
反应方程式
REACTANTS
反应物
PRODUCTS
生成物
AUXILIARIES
试剂、催化剂与溶剂
PROCEDURE
实验过程
Cholic acid, 4.08 g, is dissolved in 10 ml of dry dimethylformamide and 3.40 g of imidazole is added, followed by 3.60 g of t-butyldimethylsilyl chloride. The reaction mixture is allowed to stand overnight at room temperature. The reaction mixture is poured into water, filtered and the precipitate is washed with water. This precipitate is dissolved in 30 ml of tetrahydrofuran and 3 ml of water and 2 ml of acetic acid is added. After 6.5 hours, the solvent is evaporated and the residue chromatographed on 200 g of silica gel with 5% methanol in methylene chloride as eluent, to provide 3α-(t-butyldimethylsilyloxy)-7α,12α-dihydroxy-5β-cholan-24-oic acid, mp 145.5-148, having the following structural formula: ##STR14##
WORKUP
后处理
- filtrationfiltered
- washthe precipitate is washed with water
- dissolutionThis precipitate is dissolved in 30 ml of tetrahydrofuran
- addition3 ml of water and 2 ml of acetic acid is added
- waitAfter 6.5 hours
- customthe solvent is evaporated
- customthe residue chromatographed on 200 g of silica gel with 5% methanol in methylene chloride as eluent