Diethyl Malonate → diethyl 2-[(4-nitrophenyl)methyl]propanedioate

Temperature

45 °C

4-Nitrobenzyl bromide 22 (10.57 g, 48.93 mmol) was added to a solution of diethyl malonate 21 (52 mL, 54.86 g, 342.51 mmol) and K2CO3 (14.21 g, 102.8 mmol) in acetone (40 mL). The reaction mixture was heated at 45° C. for 1 hour. The mixture was allowed to cool to room temperature and the resulting yellow slurry was filtered off to remove K2CO3 and washed with acetone (2×20 mL). The solvent was evaporated from the combined filtrate and washings under reduced pressure. The excess of diethylmalonate was removed by horizontal distillation (2 hr, 80-130° C., and 0.005 mbar). The yellow oily residue was dissolved in ethanol (200 mL). The precipitated white solid (dialkylated product) was filtered and washed with ethanol (2×20 mL). The solvent was evaporated from the combined filtrate and washings under reduced pressure to give a solid, which was recrystallized from hexane/Et2O (1:1) to afford white crystalline needles 23 (12.72 g, 88% yield).

1. temperatureto cool to room temperature
2. filtrationthe resulting yellow slurry was filtered off
3. customto remove K2CO3
4. washwashed with acetone (2×20 mL)
5. customThe solvent was evaporated from the combined filtrate and washings under reduced pressure
6. customThe excess of diethylmalonate was removed by horizontal distillation (2 hr, 80-130° C., and 0.005 mbar)
7. dissolutionThe yellow oily residue was dissolved in ethanol (200 mL)
8. filtrationThe precipitated white solid (dialkylated product) was filtered
9. washwashed with ethanol (2×20 mL)
10. customThe solvent was evaporated from the combined filtrate and washings under reduced pressure
11. customto give a solid, which
12. customwas recrystallized from hexane/Et2O (1:1)

ORD record

ord-5dffa42eb0d0474693a71003351c54a4

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09061078B2