反应详情

温度

0 °C

A solution of 9-fluorenylmethoxycarbonyl chloride (1.4 g; 5.4 mmol) in 1,4-dioxane (18 mL) was added dropwise to a suspension of (3β,5β,7α,12α)-3-amino-7,12-dihydroxycholan-24-oic acid A (2.0 g; 4.9 mmol) (3) in 10% aq. Na2CO3 (30 mL) and 1,4-dioxane (18 mL) stirred at 0° C. After 6 h stirring at room temperature H2O (100 mL) was added, the aqueous phase washed with Et2O (2×90 mL) and then 2 M HCl (15 mL) was added (final pH: 1.5). The precipitated solid was filtered, washed with H2O (3×100 mL), vacuum dried and then purified by flash chromatography to give B as a white solid (2.2 g; 3.5 mmol). Yield 71%.

1. additionwas added
2. washthe aqueous phase washed with Et2O (2×90 mL)
3. addition2 M HCl (15 mL) was added (final pH: 1.5)
4. filtrationThe precipitated solid was filtered
5. washwashed with H2O (3×100 mL), vacuum
6. customdried
7. custompurified by flash chromatography
8. customto give B as a white solid (2.2 g; 3.5 mmol)