Diethyl methylmalonate → Diethyl 2-(4-bromobenzyl)-2-methylmalonate

HRID 1384216Notes

Reaction equation

HRID 1384216 reaction equation
[O-]CC.[Na+].[Na].[CH3:6][CH:7]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[C:8]([O:10][CH2:11][CH3:12])=[O:9].[Br:18][C:19]1[CH:26]=[CH:25][C:22]([CH2:23]Br)=[CH:21][CH:20]=1>C(O)C>[Br:18][C:19]1[CH:26]=[CH:25][C:22]([CH2:23][C:7]([CH3:6])([C:8]([O:10][CH2:11][CH3:12])=[O:9])[C:13]([O:15][CH2:16][CH3:17])=[O:14])=[CH:21][CH:20]=1

Participants

6

Reactant 4

HCID 11857Diethyl methylmalonateHCID 685274-Bromobenzyl bromideHCID 2723922Sodium ethoxideHCID 5360545Sodium

Product 1

HCID 21186275Diethyl 2-(4-bromobenzyl)-2-methylmalonate

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
5 °C

Procedure

Sodium ethoxide was generated by the addition of sodium (9.45 g) to ethanol (370 ml). The resulting solution was cooled to 5° C. and diethyl 2-methylmalonate (68.8 ml) added over 2 minutes. The reaction mixture was stirred at 5° C. for 20 minutes and then 4-bromobenzyl bromide (97.0 g) was added over 20 minutes. The reaction mixture was then heated under reflux for 16 hours. The reaction mixture was cooled to ambient temperature, filtered through diatomaceous earth and evaporated. The residue was partitioned between water (500 ml) and diethyl ether (1000 ml). The diethyl ether was separated and the aqueous layer was extracted with diethyl ether (2×500 ml). The combined organic layers were dried (MgSO4) and evaporated to give an amber oil. This was purified by vacuum distillation, affording diethyl 2-(4-bromobenzyl)-2-methylmalonate (84.4 g), b.p.122-125° C./0.1-0.2 mm Hg; mass spectrum (+ve CI): 343 (M+H)+.

Workup

  1. temperatureThe reaction mixture was then heated
  2. temperatureunder reflux for 16 hours
  3. temperatureThe reaction mixture was cooled to ambient temperature
  4. filtrationfiltered through diatomaceous earth
  5. customevaporated
  6. customThe residue was partitioned between water (500 ml) and diethyl ether (1000 ml)
  7. customThe diethyl ether was separated
  8. extractionthe aqueous layer was extracted with diethyl ether (2×500 ml)
  9. dry with materialThe combined organic layers were dried (MgSO4)
  10. customevaporated
  11. customto give an amber oil
  12. distillationThis was purified by vacuum distillation

Sources & evidence

ORD record
ord-600ec725ba384558ad8b05367a1ba503
Source dataset
uspto-grants-2001_07
Patent number
US06258817B1

Reaction notes

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