Potassium Bromide → 2,5-bis(4-Bromophenyl)-3-(p-tolyloxy)furan

HRID 792

Reaction equation

HRID 792 reaction equation
[C:1]1([CH3:28])[CH:6]=[CH:5][C:4]([O:7][C:8]([C:19](=O)[C:20]2[CH:25]=[CH:24][C:23]([Br:26])=[CH:22][CH:21]=2)=[CH:9][C:10](=[O:18])[C:11]2[CH:16]=[CH:15][C:14]([Br:17])=[CH:13][CH:12]=2)=[CH:3][CH:2]=1.[K+].[Br-]>P(Cl)(Cl)Cl>[Br:26][C:23]1[CH:22]=[CH:21][C:20]([C:19]2[O:18][C:10]([C:11]3[CH:12]=[CH:13][C:14]([Br:17])=[CH:15][CH:16]=3)=[CH:9][C:8]=2[O:7][C:4]2[CH:3]=[CH:2][C:1]([CH3:28])=[CH:6][CH:5]=2)=[CH:25][CH:24]=1

Participants

4

Reactant 2

HCID 253877Potassium BromideHCID 539578091-(4-Tolyloxy)-1,2-bis-(4-bromobenzoyl)ethylene

Product 1

HCID 103452192,5-bis(4-Bromophenyl)-3-(p-tolyloxy)furan

Reagents, catalysts & solvents 1

HCID 24387Phosphorus trichlorideSolvent

Procedure

A solution of 5.0 g (0.01 mole) 1-(4-tolyloxy)-1,2-bis-(4-bromobenzoyl)ethylene in 10 ml phosphorus trichloride was heated under reflux for 3-4 hr (TLC followed). The excess PCl3 was removed by distillation and the residue was triturated with ice/water (exothermic reaction). The solution was extracted with dichloromethane (75 ml) and the dichloromethane layer was washed with saturated sodium bicarbonate solution, water, and dried (Na2 SO4). The solvent was removed under reduced pressure. The residual solid was chromatographed over silica gel using ether:hexane (2:8 to 1:1) as eluant. An off white crystalline solid was obtained, 2.78 g (56%), mp 92°-3° C. IR (KBr) 2923, 2851, 1560, 1506, 1467, 1390, 1209, 1072, 1066, 945, 825, 707, 486. 1H NMR (CDCl3 /35° C.) 7.69 (d, 2H, J=8.8), 7.46-7.43 (m, 6H), 7.12 (d, 2H, J=8.3), 7.0 (d, 2H, J=8.3), 6.47 (s, 1H), 2.31 (s, 3H). 13C NMR (CDCl3 /135° C.) 150.8, 150.1, 142.8, 139.3, 133.0, 131.9, 131.7, 130.3, 129.1, 128.6, 125.1, 125.0, 121.8, 120.5, 117.1, 102.7, 20.6. MS m/e 484 (M+).

Workup

  1. temperatureunder reflux for 3-4 hr (TLC followed)
  2. customThe excess PCl3 was removed by distillation
  3. customthe residue was triturated with ice/water (exothermic reaction)
  4. extractionThe solution was extracted with dichloromethane (75 ml)
  5. washthe dichloromethane layer was washed with saturated sodium bicarbonate solution, water
  6. customdried (Na2 SO4)
  7. customThe solvent was removed under reduced pressure
  8. customThe residual solid was chromatographed over silica gel
  9. customAn off white crystalline solid was obtained

Sources & evidence

ORD record
ord-67300f99f22241ef9811a9c1212c4492
Source dataset
uspto-grants-1998_03
Patent number
US05723288

Linked notes

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