Catechol → 4-Fluorobenzo[d][1,3]dioxole

HRID 2063214Notes

Reaction equation

HRID 2063214 reaction equation
BrCBr.[F:4][C:5]1[CH:11]=[CH:10][CH:9]=[C:7]([OH:8])[C:6]=1[OH:12].[C:13]1(C(=CC=CC=1)O)O>[Cl-].C[N+](CCCCCCCC)(CCCCCCCC)CCCCCCCC.[OH-].[Na+].C(Cl)Cl.O>[F:4][C:5]1[CH:11]=[CH:10][CH:9]=[C:7]2[O:8][CH2:13][O:12][C:6]=12

Participants

8

Reactant 3

HCID 289CatecholHCID 3024DibromomethaneHCID 677643-Fluorocatechol

Product 1

HCID 157672604-Fluorobenzo[d][1,3]dioxole

Reagents, catalysts & solvents 4

HCID 21218Trioctylmethylammonium chlorideCatalystHCID 962WaterSolvent2×HCID 6344DichloromethaneSolventHCID 14798Sodium HydroxideSolvent

Procedure

Alliquat 336 (methyltrioctylammonium chloride (0.63 g, 0.0016 mol), dibromomethane (40.7 g, 234.2 mmol), and water (31 mL) were placed in a 500 mL 3-necked flask equipped with an addition funnel, condenser and a stir bar. The addition funnel was charged with a solution of 3-fluorocatechol (20.0 g, 6.1 mmol) in 5M sodium hydroxide (80 mL). The mixture in the flask was heated to reflux and the solution of the catechol was added dropwise with good stirring over 1.5 hours. The resulting dark mixture was heated an additional 2 hours at reflux. After cooling to room temperature, the reaction was diluted with methylene chloride and water. The aqueous layer was extracted with methylene chloride and the combined organic layers were dried and concentrated to give 1-fluoro-2,3-methylenedioxybenzene (14.6 g, 104.2 mmol) as a dark yellow oil: 1H NMR (CDCl3): δ 6.80 (m, 1H), 6.68 (m, 2H), 6.04 (s, 2H).

Workup

  1. customequipped with an addition funnel, condenser and a stir bar
  2. temperatureThe mixture in the flask was heated
  3. temperatureto reflux
  4. temperatureThe resulting dark mixture was heated an additional 2 hours
  5. temperatureat reflux
  6. extractionThe aqueous layer was extracted with methylene chloride
  7. customthe combined organic layers were dried
  8. concentrationconcentrated

Sources & evidence

ORD record
ord-e70e6895532d4a47ac160de81e9c793d
Source dataset
uspto-grants-2012_10
Patent number
US08288318B2

Reaction notes

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