Diethyl Malonate → Diethyl 2-vinylcyclopropane-1,1-dicarboxylate

HRID 2174445Notes

Reaction equation

HRID 2174445 reaction equation
[C:1]([O:9][CH2:10][CH3:11])(=[O:8])[CH2:2][C:3]([O:5][CH2:6][CH3:7])=[O:4].C(O)C.[O-]CC.[Na+].Br[CH2:20]/[CH:21]=[CH:22]/[CH2:23]Br.[OH-].[Na+]>C1(C)C=CC=CC=1>[CH2:10]([O:9][C:1]([C:2]1([C:3]([O:5][CH2:6][CH3:7])=[O:4])[CH2:23][CH:22]1[CH:21]=[CH2:20])=[O:8])[CH3:11]

Participants

6

Reactant 4

HCID 7761Diethyl MalonateHCID 14798Sodium HydroxideHCID 641245trans-1,4-Dibromo-2-butene2×HCID 23706232Ethanol sodium ethoxide2×

Product 1

HCID 111025Diethyl 2-vinylcyclopropane-1,1-dicarboxylateYield 168.5%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

93.4 g (583 mmol) of diethyl malonate and 1000 mL of toluene 1000 mL were added into a four-necked flask (2 L), and thereafter, 223 mL (569 mmol) of a 20% sodium ethoxide ethanol solution was added thereto as a base. The obtained mixture was stirred at room temperature for 1.5 hours, and 59.4 g of trans-1,4-dibromo-2-butene (278 mmol; a reagent manufactured by Aldrich) was then added to the reaction solution. The obtained mixture was stirred at room temperature for 2 hours, and 109 mL (278 mmol) of a 20% sodium ethoxide ethanol solution was further added to the reaction solution. The mixture was stirred at room temperature for 1 hour, and 29.1 g of trans-1,4-dibromo-2-butene (136 mmol; a reagent manufactured by Aldrich) was then added thereto. The thus obtained mixture was stirred at room temperature for 4 hours, and 347 mL of a 1 M sodium hydroxide aqueous solution was then added thereto. The mixture was stirred for 14 hours, and an organic layer was then separated. Subsequently, the organic layer was washed with 132 mL of water twice, and it was then dried over anhydrous sodium sulfate, followed by filtration. The obtained filtrate was concentrated at 40° C. under reduced pressure, so as to obtain 99.3 g of 1,1-di-ethoxycarbonyl-2-vinylcyclopropane in the form of a crude product of a light yellow oily substance. This crude product contained 83.2 g of 1,1-di-ethoxycarbonyl-2-vinylcyclopropane (yield: 94.9%). In addition, it contained no diethyl malonates.

Workup

  1. additionwas then added to the reaction solution
  2. stirringThe obtained mixture was stirred at room temperature for 2 hours
  3. stirringThe mixture was stirred at room temperature for 1 hour
  4. additionwas then added
  5. stirringThe thus obtained mixture was stirred at room temperature for 4 hours
  6. stirringThe mixture was stirred for 14 hours
  7. customan organic layer was then separated
  8. washSubsequently, the organic layer was washed with 132 mL of water twice
  9. dry with materialit was then dried over anhydrous sodium sulfate
  10. filtrationfollowed by filtration
  11. concentrationThe obtained filtrate was concentrated at 40° C. under reduced pressure

Sources & evidence

ORD record
ord-ea58536635124d59af41ff54c5b68c45
Source dataset
uspto-grants-2015_06
Patent number
US09061991B2

Reaction notes

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