反应详情

温度

20 °C

4.2 ml of trimethylsilyl-diazomethane are added dropwise at a temperature of −10° C. to a solution of 1.91 g (7 mmol) of 5-bromo-7,8-dioxo-bicyclo[2.2.2]oct-5-ene-2-carboxylic acid methyl ester in 20 ml of dichloromethane and 0.089 ml (0.7 mmol) of boron trifluoride etherate. The cooling is removed and the reaction mixture is stirred for 4 hours at a temperature of 20° C. The reaction solution is then extracted with water, the organic phase is dried over sodium sulfate and concentrated by evaporation using a rotary evaporator, and the residue is purified by silica gel chromatography. An isomer of 8-bromo-2,4-dioxo-bicyclo[3.2.2]non-8-ene-6-carboxylic acid methyl ester is obtained.

1. customThe cooling is removed
2. extractionThe reaction solution is then extracted with water
3. dry with materialthe organic phase is dried over sodium sulfate
4. concentrationconcentrated by evaporation
5. customa rotary evaporator
6. customthe residue is purified by silica gel chromatography