Diketene → HCID 12525205, compound

HRID 127029Notes

Reaction equation

HRID 127029 reaction equation
[Br:1][C:2]([Br:10])([Br:9])[CH:3]([OH:8])[CH:4]=[C:5]([CH3:7])[CH3:6].[CH2:11]=[C:12]1[O:16][C:14](=[O:15])[CH2:13]1>CCOCC.C([O-])(=O)C.[Na+]>[C:14]([O:8][CH:3]([C:2]([Br:10])([Br:9])[Br:1])[CH:4]=[C:5]([CH3:7])[CH3:6])(=[O:15])[CH2:13][C:12]([CH3:11])=[O:16]

Participants

5

Reactant 2

HCID 12661DiketeneHCID 125252021,1,1-Tribromo-4-methylpent-3-en-2-ol

Product 1

HCID 12525205HCID 12525205, compoundYield 99.1%

Reagents, catalysts & solvents 2

HCID 517045Sodium AcetateCatalystHCID 3283Diethyl EtherSolvent

Procedure

1,1,1-Tribromo-4-methyl-3-penten-2-ol (6.72 g, 0.02 mole) and anhydrous sodium acetate (0.008 g) were melted together at 90°. The temperature of the mixture was then reduced to 80°, and diketene (about 2.6 ml, 0.022 mole) was added dropwise over a 10 minute period. The resulting mixture was heated at 80° for three additional hours. After cooling, the mixture was diluted with ether, and the ethereal solution was washed with 1 N aqueous hydrochloric acid and then ten times with saturated aqueous sodium bicarbonate. The washed mixture was treated with activated charcoal and dried over magnesium sulfate. Evaporation of the ether afforded 3-methyl-1-tribromomethyl-2-butenyl acetoacetate (8.34 g, 99% yield) as an oily residue.

Workup

  1. customwere melted together at 90°
  2. customwas then reduced to 80°
  3. temperatureThe resulting mixture was heated at 80° for three additional hours
  4. temperatureAfter cooling
  5. washthe ethereal solution was washed with 1 N aqueous hydrochloric acid
  6. additionThe washed mixture was treated with activated charcoal
  7. dry with materialdried over magnesium sulfate
  8. customEvaporation of the ether

Sources & evidence

ORD record
ord-0ce087fa668f43dc86df6cc04245bea5
Source dataset
uspto-grants-1981_03
Patent number
US04254282

Reaction notes

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