HRID1816481
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
CONDITIONS
反应条件
- 温度
- 65 °C
PROCEDURE
实验过程
3β-Hydroxy-4,4-dimethyl-5α-chola-8,14-dien-24-oic acid methyl ester (18.2 g) is suspended in 400 ml of DMF and 14.8 g of imidazol and 13.0 g of t-butyldimethylsilylchloride is added. The reaction is stirred at 65° C. for 20 hours. After aqueous work-up and crystallization from ether/methanol, 3β-tert-butyldimethylsilyloxy-4,4-dimethyl-5α-chola-8,14-dien-24-oic acid methyl ester (21 g) is obtained. Melting point: 124-125° C. 1H-NMR (CDCl3, 400 MHz): δ=5.34 (1H, s); 3.68 (3H, s); 3.2 (1H, m); 0.9 (9H, s); 0.04 (6H, m).
WORKUP
后处理
- customAfter aqueous work-up and crystallization from ether/methanol