1-Bromo-2-methylpropane → Diethyl isobutylmalonate

HRID 129719Notes

Reaction equation

HRID 129719 reaction equation
CC[O-].[Na+].[C:5]([O:13][CH2:14][CH3:15])(=[O:12])[CH2:6][C:7]([O:9][CH2:10][CH3:11])=[O:8].[CH2:16](Br)[CH:17]([CH3:19])[CH3:18]>CCO>[CH2:16]([CH:6]([C:7]([O:9][CH2:10][CH3:11])=[O:8])[C:5]([O:13][CH2:14][CH3:15])=[O:12])[CH:17]([CH3:19])[CH3:18]

Participants

5

Reactant 3

HCID 65551-Bromo-2-methylpropaneHCID 7761Diethyl MalonateHCID 2723922Sodium ethoxide

Product 1

HCID 25047Diethyl isobutylmalonateYield 88%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To a solution of NaOEt prepared by dissolving 5.75 g (0.25 mol) of Na in 150 mL of absolute EtOH was added 39 mL (0.250 mol) of diethyl malonate with cooling in a water bath under N2. To the resulting solution was added 24 mL (0.250 mol) of isobutyl bromide. The mixture was refluxed under N2 for 14 hours. The ethanol was evaporated under reduced pressure and the residue was partitioned between CHCl3 and water. The aqueous Na2SO4 and evaporated. The residue was distilled under reduced pressure to give 47.2 g (0.219 mol, 88% of diethyl isobutylmalonate as a colorless liquid. Characteristic analytical data are as follows: bp 127°-135° C. (25 mm Hg); 1H NMR (300 MHz, CDCL3) δ4.20 (q, J=7 Hz, 4H), 3,41 (t, J=8 Hz, 1H), 1.80 (t, J=7 Hz, 2 H), 1.57 (m, 1H), 1.27 (t, J=8 Hz, 6H), 0.92 (d, J=7 Hz, 6H).

Workup

  1. temperaturewith cooling in a water bath under N2
  2. temperatureThe mixture was refluxed under N2 for 14 hours
  3. customThe ethanol was evaporated under reduced pressure
  4. customthe residue was partitioned between CHCl3 and water
  5. customThe aqueous Na2SO4 and evaporated
  6. distillationThe residue was distilled under reduced pressure

Sources & evidence

ORD record
ord-dff8ef8195a54140aa73422758901936
Source dataset
uspto-grants-1995_11
Patent number
US05470834

Reaction notes

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