Diethyl Oxalate → HCID 23319935, compound

In 100 ml of ethanol is dissolved 4.5 g of sodium, and 27.8 g of ethyl 4-ethylhexanoate and 29 g of diethyl oxalate are added to the solution, and the low-boiling substance is removed by evaporation under reduced pressure at about 70° C. for 40 minutes. After cooling, 500 ml of water and 300 ml of petroleum ether are added to the brown viscous residue, and the mixture is thoroughly shaken. The aqueous layer is separated off and the petroleum layer is extracted twice with 50 ml each of 1N sodium hydroxide solution. The extracts are combined, acidified slightly with concentrated hydrochloric acid and extracted twice with 200 ml each of ethyl acetate. The extract is dried over anhydrous magnesium sulfate and concentrated under reduced pressure. One hundred and ten (110) ml of 10% aqueous dimethylsulfoxide and 10 g of sodium chloride are added to the oily residue, and the mixture is stirred at 160° C. for 2.5 hours. After the reaction mixture is cooled, 500 ml of water is added, followed by extraction with 300 ml of ethyl acetate. The extract is washed with water, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The brown oily residue is distilled under reduced pressure to give 16.4 g of ethyl 5-ethyl-2-oxoheptanoate as a pale yellow oil.

1. additionare added to the solution
2. customthe low-boiling substance is removed by evaporation under reduced pressure at about 70° C. for 40 minutes
3. temperatureAfter cooling
4. addition500 ml of water and 300 ml of petroleum ether are added to the brown viscous residue
5. customThe aqueous layer is separated off
6. extractionthe petroleum layer is extracted twice with 50 ml each of 1N sodium hydroxide solution
7. extractionextracted twice with 200 ml each of ethyl acetate
8. dry with materialThe extract is dried over anhydrous magnesium sulfate
9. concentrationconcentrated under reduced pressure
10. additionOne hundred and ten (110) ml of 10% aqueous dimethylsulfoxide and 10 g of sodium chloride are added to the oily residue
11. stirringthe mixture is stirred at 160° C. for 2.5 hours
12. temperatureAfter the reaction mixture is cooled
13. addition500 ml of water is added
14. extractionfollowed by extraction with 300 ml of ethyl acetate
15. washThe extract is washed with water
16. dry with materialdried over anhydrous magnesium sulfate
17. concentrationconcentrated under reduced pressure
18. distillationThe brown oily residue is distilled under reduced pressure

ORD record

ord-fc71c9e33bbd448ba36857bfd8a202ed

Source dataset

uspto-grants-1986_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04591458