반응 #446027

반응 방정식

CO2

cyclopropanecarboxylic acid

pyridine-2,3-dicarboxylic acid diethyl ester

→

6-cyclopropyl-pyridine-2,3-dicarboxylic acid diethyl ester

용매

water

water

sulphuric acid

반응 조건

후처리

1. 1
   온도the reaction mixture is heated to 70°
2. 2
   workup.STIRRINGthe reaction mixture is stirred for a further 20 minutes
3. 3
   온도It is then cooled to 15°
4. 4
   추출extracted twice with 200 ml of methylene chloride each time
5. 5
   기타The organic phase is collected
6. 6
   건조dried over magnesium sulphate
7. 7
   여과filtered
8. 8
   농축concentrated by evaporation
9. 9
   workup.DISTILLATIONThe residue is distilled at 13 millibars
10. 10
    workup.DISTILLATIONthe distillate is chromatographed over a column of silica gel with hexane/methylene chloride/ether
11. 11
    기타After the solvent has been evaporated 11.2 g of the above diester

실험 절차

40 g of pyridine-2,3-dicarboxylic acid diethyl ester are dissolved in a mixture of 400 g of water and 36 g of concentrated sulphuric acid and 6.1 g of silver nitrate (AgNO3). Subsequently, 32 g of cyclopropanecarboxylic acid are added and the reaction mixture is heated to 70°. A solution of 82.1 g of ammonium peroxydisulphate (NH4)2S2O8 in 300 ml of water is added dropwise thereto while stirring vigorously. When the evolution of CO2 has ceased, the reaction mixture is stirred for a further 20 minutes. It is then cooled to 15° and extracted twice with 200 ml of methylene chloride each time. The organic phase is collected, dried over magnesium sulphate, filtered and concentrated by evaporation. The residue is distilled at 13 millibars and the distillate is chromatographed over a column of silica gel with hexane/methylene chloride/ether. After the solvent has been evaporated 11.2 g of the above diester remain behind in the form of a colourless oil.

출처