1,3-Dibromopropane → 7-Bromo-8-fluoro-3,4-dihydro-2H-benzo-[1,4]-dioxepine

HRID 1754061Notes

Reaction equation

HRID 1754061 reaction equation
[Br:1][C:2]1[CH:3]=[C:4](O)[C:5]([OH:9])=[CH:6][C:7]=1[F:8].[C:11]([O-])([O-])=[O:12].[Cs+].[Cs+].BrC[CH2:19][CH2:20]Br>CN(C=O)C>[Br:1][C:2]1[C:7]([F:8])=[CH:6][C:5]2[O:9][CH2:20][CH2:19][O:12][CH2:11][C:4]=2[CH:3]=1

Participants

5

Reactant 3

HCID 80011,3-DibromopropaneHCID 10796Cesium carbonateHCID 218653784-Bromo-5-fluorobenzene-1,2-diol

Product 1

HCID 896220067-Bromo-8-fluoro-3,4-dihydro-2H-benzo-[1,4]-dioxepine

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
120 °C

Procedure

To 1.50 g (7.25 mmol) of 4-bromo-5-fluorobenzene-1,2-diol in 25 ml DMF are added 5.90 g (18.1 mmol) Cs2CO3 and 0.89 ml (8.70 mmol) 1,3-dibromopropane. The reaction mixture is stirred at 120° C. over night. The solvent is removed in vacuo and to the residue is added water. After extracting with EtOAc the org. phases are combined, washed with sat. aq. NaCl solution and dried over MgSO4. The solvent is removed in vacuo and the resulting residue is purified by column chromatography (silica gel, PE/EtOAc 9/1→7/3).

Workup

  1. customThe solvent is removed in vacuo and to the residue
  2. additionis added water
  3. extractionAfter extracting with EtOAc the org
  4. washwashed with sat. aq. NaCl solution
  5. dry with materialdried over MgSO4
  6. customThe solvent is removed in vacuo
  7. customthe resulting residue is purified by column chromatography (silica gel, PE/EtOAc 9/1→7/3)

Sources & evidence

ORD record
ord-f1748e75296d410dba083920eea77c53
Source dataset
uspto-grants-2015_10
Patent number
US09169205B2

Reaction notes

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