Dimethylformamide → Diethyl ethylmethylmalonate

To a stirred solution of 40.0 grams (0.23 mole) of diethyl 2-methylmalonate and 50.2 grams (0.46 mole) of bromoethane in 200 ml of dry dimethylformamide was added 79.5 grams (0.58 mole) of potassium carbonate. The resulting mixture was stirred at ambient temperature for 16 hours. A sample of the reaction mixture was subjected to analysis by vapor phase chromatography (VPC), which indicated the reaction had not gone to completion. An additional 50.2 grams of bromoethane was added and the reaction mixture stirred at ambient temperature for three days. VPC analysis indicated the reaction to be 80.9% complete. The reaction mixture was heated to 50° C. where it was stirred for one day. VPC analysis at this time indicated the reaction to be 88.8% complete. The reaction mixture was filtered and the filter cake washed with 200 ml of methylene chloride. The filtrate was diluted with 500 ml of methylene chloride and the combination washed with three portions of 500 ml each of water. The organic layer was dried with magnesium sulfate and filtered. The filtrate was concentrated under reduced pressure to a residual oil. The oil was distilled under reduced pressure to give 40.9 grams of diethyl 2-ethyl-2-methylmalonate; bp 109°-112° C./25 mm. The nmr and ir spectra were consistent with the assigned structure.

1. stirringthe reaction mixture stirred at ambient temperature for three days
2. customthe reaction
3. temperatureThe reaction mixture was heated to 50° C. where it
4. stirringwas stirred for one day
5. customthe reaction
6. filtrationThe reaction mixture was filtered
7. washthe filter cake washed with 200 ml of methylene chloride
8. additionThe filtrate was diluted with 500 ml of methylene chloride
9. washthe combination washed with three portions of 500 ml each of water
10. dry with materialThe organic layer was dried with magnesium sulfate
11. filtrationfiltered
12. concentrationThe filtrate was concentrated under reduced pressure to a residual oil
13. distillationThe oil was distilled under reduced pressure

ORD record

ord-ceed81b1809f43a4a222d63f58312af4

Source dataset

uspto-grants-1981_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04302238