Dibromodifluoromethane → 4,4-Difluoro-3-methyl-3-butenyl benzoate

HRID 917398Notes

Reaction equation

HRID 917398 reaction equation
O1CCCC1.Br[C:7](Br)([F:9])[F:8].CN(P(N(C)C)N(C)C)C.O=[C:22]([CH3:34])[CH2:23][CH2:24][O:25][C:26](=[O:33])[C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1>C(OCC)C>[C:26]([O:25][CH2:24][CH2:23][C:22]([CH3:34])=[C:7]([F:9])[F:8])(=[O:33])[C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1

Participants

6

Reactant 4

HCID 6382DibromodifluoromethaneHCID 8028Tetrahydrofuran2×HCID 15355Hexamethylphosphorous triamideHCID 108994682-Butanone, 4-(benzoyloxy)-

Product 1

HCID 230202264,4-Difluoro-3-methyl-3-butenyl benzoateYield 72.5%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

Reaction was carried out under nitrogen atmosphere. To 400 ml of tetrahydrofuran, 46.2 g (0.22 mol) of dibromodifluoromethane was dissolved, followed by drop-wise adding 70.2 g (0.43 mol) of tris (dimethylamino)phosphine at −10° C. After the end of the drop-wise addition, the reaction liquid was stirred at room temperature for 1 hour, and 150 ml tetrahydrofuran solution dissolving with 19.2 g (0.10 mol) of 3-oxobutylbenzoate was further added drop-wise at −20° C. After the end of the drop-wise addition, the reaction liquid was stirred at room temperature overnight. To this mixture, diethyl ether was added, followed by washing with dilute hydrochloric acid, a saturated aqueous solution of sodium hydrogencarbonate and a saturated saline solution in this order, followed by drying over anhydrous magnesium sulfate, and concentrating under reduced pressure. The residue was purified by silica gel column chromatography (diisopropyl ether:hexane=1:8) to obtain 16.4 g (yield: 72%) of 4,4-difluoro-3-methyl-3-butenyl benzoate.

Workup

  1. customReaction
  2. additionAfter the end of the drop-wise addition
  3. customthe reaction liquid
  4. customat −20° C
  5. additionAfter the end of the drop-wise addition
  6. customthe reaction liquid
  7. stirringwas stirred at room temperature overnight
  8. washby washing with dilute hydrochloric acid
  9. dry with materialby drying over anhydrous magnesium sulfate
  10. concentrationconcentrating under reduced pressure
  11. customThe residue was purified by silica gel column chromatography (diisopropyl ether:hexane=1:8)

Sources & evidence

ORD record
ord-d7a5399a1a6c4112b678695441686c0e
Source dataset
uspto-grants-2007_09
Patent number
US07273878B2

Reaction notes

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