反应详情

A mixture of 4.0 g of KOH in 50 ml of ethanol was added at room temperature to 20 g of benzylmalonic acid diethyl ester in 40 ml of ethanol. The mixture was stirred overnight at room temperature, then concentrated by evaporation, thereafter 7.1 ml of water was added and then the mixture was acidified in an ice bath with 6.3 ml of concentrated hydrochloric acid. Partitioning between water and ether was carried out, the organic phase was dried and the ether was distilled off. Then, 12.9 ml of pyridine, 0.61 g of piperidine and 1.78 g of paraformaldehyde were added to the residue. The mixture was heated in an oil bath (130° ) for 90 minutes, cooled, 220 ml of water was added and extraction was carried out 3 times with 75 ml of n-hexane. The combined organic phases were washed alternatively with water, 1N HCl, water, saturated NaHCO3 solution and brine. The solution was dried (MgSO4) and evaporated to give the title compound as colorless oil (26 g, 85% yield) 1H NMR: 300 MHz; spectrum consistent with proposed structure.

1. concentrationconcentrated by evaporation
2. addition7.1 ml of water was added
3. customthe mixture was acidified in an ice bath with 6.3 ml of concentrated hydrochloric acid
4. customPartitioning between water and ether
5. customthe organic phase was dried
6. distillationthe ether was distilled off
7. additionThen, 12.9 ml of pyridine, 0.61 g of piperidine and 1.78 g of paraformaldehyde were added to the residue
8. temperatureThe mixture was heated in an oil bath (130° ) for 90 minutes
9. temperaturecooled
10. addition220 ml of water was added
11. extractionextraction
12. washThe combined organic phases were washed alternatively with water, 1N HCl, water, saturated NaHCO3 solution and brine
13. dry with materialThe solution was dried (MgSO4)
14. customevaporated