反应详情

A solution of the product of example 5, step (c) (10.5 g) in acetonitrile (50 ml) and triethylamine (17 ml) was added to an ice cold stirred solution of ethoxycarbonylisothiocyanate (3 ml) in acetonitrile (50 ml). This mixture was then stirred at room temperature for 20 min. Diisopropylcarbodiimide (4.5 ml) was then added and the reaction mixture was stirred at reflux for 2 hr and allowed to cool. The reaction mixture was evaporated to dryness and purified by flash chromatography on silica gel (ethyl acetate:dichloromethane, 1:1) to yield the sub-titled compound as a yellow solid (3.0 g).

1. stirringthe reaction mixture was stirred
2. temperatureat reflux for 2 hr
3. temperatureto cool
4. customThe reaction mixture was evaporated to dryness
5. custompurified by flash chromatography on silica gel (ethyl acetate:dichloromethane, 1:1)