Potassium Carbonate → 2,2,3,3-Tetrafluoro-2,3-dihydro-1,4-benzodioxin-5-amine

HRID 257228Notes

Reaction equation

HRID 257228 reaction equation
Br[C:2]1[C:15](Br)=[CH:14][C:5]2[O:6][C:7]([F:13])([F:12])[C:8]([F:11])([F:10])[O:9][C:4]=2[C:3]=1[N+:17]([O-])=O.C(=O)([O-])[O-].[K+].[K+].[H][H]>CO.[C].[Pd]>[NH2:17][C:3]1[C:4]2[O:9][C:8]([F:10])([F:11])[C:7]([F:13])([F:12])[O:6][C:5]=2[CH:14]=[CH:15][CH:2]=1

Participants

6

Reactant 3

HCID 11430Potassium CarbonateHCID 22910002HCID 22910002, compoundHCID 178418361HCID 178418361, compound

Product 1

HCID 27765722,2,3,3-Tetrafluoro-2,3-dihydro-1,4-benzodioxin-5-amineYield 78%

Reagents, catalysts & solvents 2

HCID 178418390HCID 178418390, compoundCatalystHCID 887MethanolSolvent

Procedure

62 g (150 mmol) of 6,7-dibromo-5-nitro-2,2,3,3-tetrafluoro-benzo(1.4)dioxane, 41 g (300 mmol) of potassium carbonate and 5 g of palladium-carbon (10% strength) are stirred at 50° C. and a hydrogen pressure of 90 bar in 500 ml of methanol in an autoclave for 20 hours. The reaction mixture is filtered, the filtrate is mixed with 500 ml of water and extracted thoroughly with ether, and the extract is dried over sodium sulphate and concentrated. Vacuum distillation yields 26 g (78% of theory) of 5-amino-2,2,3,3-tetrafluoro-benzo(1.4)dioxane having a boiling point of 99° to 101° C./16 mm.

Workup

  1. filtrationThe reaction mixture is filtered
  2. additionthe filtrate is mixed with 500 ml of water
  3. extractionextracted thoroughly with ether
  4. dry with materialthe extract is dried over sodium sulphate
  5. concentrationconcentrated
  6. distillationVacuum distillation

Sources & evidence

ORD record
ord-dbbd5c10647747e7adefb9d7f888b200
Source dataset
uspto-grants-1993_11
Patent number
US05260460

Reaction notes

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