Hydrochloric Acid → Ethyl 3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate

HRID 1449032Notes

Reaction equation

HRID 1449032 reaction equation
Cl[C:2](Cl)=[CH:3][CH:4]1[CH:6]([C:7]([O:9][CH2:10][CH3:11])=[O:8])[C:5]1([CH3:13])[CH3:12].[Br-:15].[Al+3].[Br-:17].[Br-].N12CCCCC1C=NCCC2.Cl>C(Br)CBr.CCCCCC.CN(C)C=O.O>[Br:15][C:2]([Br:17])=[CH:3][CH:4]1[CH:6]([C:7]([O:9][CH2:10][CH3:11])=[O:8])[C:5]1([CH3:13])[CH3:12]

Participants

9

Reactant 4

HCID 313Hydrochloric AcidHCID 101094Cyclopropanecarboxylic acid, 3-(2,2-dichloroethenyl)-2,2-dimethyl-, ethyl esterHCID 166749BromhydrolHCID 3141121,5-Diazabicyclo(5,4,0)undec-5-ene

Product 1

HCID 12550018Ethyl 3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylateYield 87%

Reagents, catalysts & solvents 4

HCID 962WaterSolventHCID 6228DimethylformamideSolventHCID 78391,2-DibromoethaneSolvent2×HCID 8058HexaneSolvent

Procedure

To a solution of ethyl 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate (14.81 g, 0.0625 mole) in 30 ml of ethylene bromide was added dropwise at 0° a solution of aluminum bromide (25 g, 0.094 mole) in 20 ml of ethylene bromide. After stirring for 41/2 hours, the solution was poured into a mixture of ice and water. The resultant mixture was extracted three times with ether. The ether extracts were combined and successively washed twice with water, twice with aqueous sodium bicarbonate, twice with aqueous sodium chloride, and then dried over anhydrous magnesium sulfate. The ether was then removed by evaporation, leaving a residue. The residue was dissolved in n-hexane, and 1,5-diazabicyclo[5.4.0] undec-5-ene was added to the solution. Dimethylformamide was added as a cosolvent. The solution was poured into dilute aqueous hydrochloric acid at 0°. The resultant mixture was extracted with ether. The ether extract was washed with water, aqueous sodium bicarbonate, aqueous sodium chloride, and then dried. The ether was removed, and the residue was distilled under reduced pressure to afford ethyl 3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate (16.28 g, 87% yield); bp, 104-106°/0.28 mm.

Workup

  1. extractionThe resultant mixture was extracted three times with ether
  2. washsuccessively washed twice with water, twice with aqueous sodium bicarbonate, twice with aqueous sodium chloride
  3. dry with materialdried over anhydrous magnesium sulfate
  4. customThe ether was then removed by evaporation
  5. customleaving a residue
  6. extractionThe resultant mixture was extracted with ether
  7. extractionThe ether extract
  8. washwas washed with water, aqueous sodium bicarbonate, aqueous sodium chloride
  9. customdried
  10. customThe ether was removed
  11. distillationthe residue was distilled under reduced pressure

Sources & evidence

ORD record
ord-2b11926d964045fd8cab6ae00d8e6f25
Source dataset
uspto-grants-1980_02
Patent number
US04188492

Reaction notes

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