Sulfuric Acid → HCID 67387644, compound

HRID 335976Notes

Reaction equation

HRID 335976 reaction equation
[Br:1][C:2]1[C:3]([F:21])=[C:4]([C:8]([O:11][C:12]2[CH:17]=[CH:16][C:15]([O:18][CH3:19])=[CH:14][C:13]=2[F:20])=[CH:9][CH:10]=1)[C:5]([OH:7])=O.S(=O)(=O)(O)O>>[Br:1][C:2]1[CH:10]=[CH:9][C:8]2[O:11][C:12]3[C:17](=[CH:16][C:15]([O:18][CH3:19])=[CH:14][C:13]=3[F:20])[C:5](=[O:7])[C:4]=2[C:3]=1[F:21]

Participants

3

Reactant 2

HCID 1118Sulfuric AcidHCID 67383345HCID 67383345, compound

Product 1

HCID 67387644HCID 67387644, compoundYield 56.6%

Conditions

Temperature
60 °C

Procedure

To a 500 mL flask was added 3-bromo-2-fluoro-6-(2-fluoro-4-methoxyphenoxy)benzoic acid (43.45 g, 121 mmol) in conc. sulfuric acid (127 mL, 1815 mmol). The sticky mixture was heated at 60° C. for 2.5 h. The reaction was then poured into ice water very slowly with stirring. The yellow precipitate was filtered through Buchner funnel and washed excess water. Then the filter cake was put in a beaker and carefully neutralized with mixture of 2N aqoueous NaOH solution and saturated aqueous NaHCO3. The mixture was stirred for half an hour and filtered by Buchner funnel again. The light yellow solid was washed by excess water and finally little amount of acetone to yield 2-bromo-1,5-difluoro-7-methoxy-9H-xanthen-9-one (23.34 g, 68.4 mmol, 56.6% yield) as light yellow solid. It was used for next step without further purification.

Workup

  1. filtrationThe yellow precipitate was filtered through Buchner funnel
  2. washwashed excess water
  3. additioncarefully neutralized with mixture of 2N aqoueous NaOH solution and saturated aqueous NaHCO3
  4. stirringThe mixture was stirred for half an hour
  5. filtrationfiltered by Buchner funnel again
  6. washThe light yellow solid was washed by excess water and finally little amount of acetone

Sources & evidence

ORD record
ord-e25c4b442fb3442cbc635a39cdf6e1b6
Source dataset
uspto-grants-2014_11
Patent number
US08883782B2

Reaction notes

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