Diethyl Malonate → 1,3-Diethyl 2-cyclopentylpropanedioate

HRID 2372535Notes

Reaction equation

HRID 2372535 reaction equation
[Na].[C:2]([O:10][CH2:11][CH3:12])(=[O:9])[CH2:3][C:4]([O:6][CH2:7][CH3:8])=[O:5].[CH:13]1(Br)[CH2:17][CH2:16][CH2:15][CH2:14]1>C(O)C>[CH:13]1([CH:3]([C:4]([O:6][CH2:7][CH3:8])=[O:5])[C:2]([O:10][CH2:11][CH3:12])=[O:9])[CH2:17][CH2:16][CH2:15][CH2:14]1

Participants

5

Reactant 3

HCID 7761Diethyl MalonateHCID 8728BromocyclopentaneHCID 5360545Sodium

Product 1

HCID 2492691,3-Diethyl 2-cyclopentylpropanedioateYield 70.6%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To a solution of 4.6 g (0.2 mol) sodium in 80 mL absolute ethanol was added 30.4 mL (0.2 mol) diethyl malonate. After briefly stirring, 21.4 mL (0.2 mol) cyclopentyl bromide was added, and the resulting solution refluxed for 12 hrs. Most of the ethanol was then removed by rotary evaporation, and the reaction was quenched with 250 mL of water and extracted 3 ×, each with 100 mL ether. The extracts were dried over MgSO4, filtered, and concentrated. Distillation through a 6" Vigreaux at 6 mm Hg provided 32.232 g of a clear colorless oil at bp 122-125 C.

Workup

  1. temperaturethe resulting solution refluxed for 12 hrs
  2. customMost of the ethanol was then removed by rotary evaporation
  3. customthe reaction was quenched with 250 mL of water
  4. extractionextracted 3 ×
  5. dry with materialThe extracts were dried over MgSO4
  6. filtrationfiltered
  7. concentrationconcentrated
  8. distillationDistillation through a 6" Vigreaux at 6 mm Hg

Sources & evidence

ORD record
ord-72eea7d8250f46838c535979d2383cf7
Source dataset
uspto-grants-1992_03
Patent number
US05099020

Reaction notes

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