反应 #362465

反应方程式

ethanol

(3S,4S)-3-[(R)-1-(trimethylsilyloxy)-ethyl]-4-[(R)-3-oxo-1,4-dithian-2-yl]azetidin-2-one

pyridine

allyl chloroglyoxylate

→

allyl [(3S,4S)-2-oxo-4-[ (R)-3-oxo-1,4-dithian-2-yl]-3-[(R)-1-(trimethylsilyloxy)ethyl]azetidin-1-yl]glyoxylate

收率 97.2%

溶剂

ether

dichloromethane

dichloromethane

dichloromethane

反应条件

后处理

1. 1
   workup.STIRRINGthe mixture was stirred for 10 minutes
2. 2
   洗涤The organic layer was washed with water, saturated copper sulfate solution and saturated aqueous sodium chloride solution in the order
3. 3
   干燥dried over anhydrous magnesium sulfate
4. 4
   workup.DISTILLATIONThe solvent was then distilled off under reduced pressure
5. 5
   其他the residue was purified by flash column chromatography (packing: silica gel; ethyl acetate-hexane=1:5)

实验过程

A solution of (3S,4S)-3-[(R)-1-(trimethylsilyloxy)-ethyl]-4-[(R)-3-oxo-1,4-dithian-2-yl]azetidin-2-one (650 mg), prepared in Reference Example 14, in dichloromethane (10 ml) was cooled at 0° C. and a solution of pyridine (483 mg) in dichloromethane (2 ml) and a solution of allyl chloroglyoxylate (603 g) in dichloromethane (3 ml) were added. The mixture was stirred at the same temperature for 2 hours. To this mixture was added ethanol (187 mg) at 0° C. and the mixture was stirred for 10 minutes, after which ether (30 ml) was added. The organic layer was washed with water, saturated copper sulfate solution and saturated aqueous sodium chloride solution in the order mentioned and dried over anhydrous magnesium sulfate. The solvent was then distilled off under reduced pressure and the residue was purified by flash column chromatography (packing: silica gel; ethyl acetate-hexane=1:5). The procedure gave allyl [(3S,4S)-2-oxo-4-[ (R)-3-oxo-1,4-dithian-2-yl]-3-[(R)-1-(trimethylsilyloxy)ethyl]azetidin-1-yl]glyoxylate as a colorless oil (853 mg).

来源