Sodium Carbonate → 3-Bromo-2-phenylthiophene

HRID 1899702Notes

Reaction equation

HRID 1899702 reaction equation
C([O-])([O-])=O.[Na+].[Na+].[C:7]1(OB(O)O)[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1.Br[C:18]1[S:19][CH:20]=[CH:21][C:22]=1[Br:23]>C(O)C.C1C=CC=CC=1.[Pd].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[Br:23][C:22]1[CH:21]=[CH:20][S:19][C:18]=1[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1

Participants

7

Reactant 3

HCID 10340Sodium CarbonateHCID 765902,3-DibromothiopheneHCID 78412Phenyl dihydrogen orthoborate

Product 1

HCID 114818273-Bromo-2-phenylthiopheneYield 47%

Reagents, catalysts & solvents 3

HCID 11979704Tetrakis(triphenylphosphine)palladiumCatalystHCID 241BenzeneSolventHCID 702EthanolSolvent

Procedure

Tetrakis (triphenylphosphine) palladium (400 mg), Na2CO3 (4M, 80 ml, 320 mmol) and phenylboric acid (3.81 g, 30.3 mmol) as a solution in ethanol (80 ml) were sequentially added to a solution of 2,3-dibromothiophene (7.33 g, 30.3 mmol) in benzene (100 ml). The mixture was heated at reflux for 12 hours. The aqueous layer of the crude mixture was removed and the organic layer was diluted with Et2O (200 ml), washed with 1N NaOH (2×150 ml) and was dried (MgSO2), filtered and the soluent was evaporated. The residue was chromatographed using hexane as the eluent to give 3-bromo-2-phenylthiophene as a clear oil (3.31 g, 47% yield).

Workup

  1. temperatureThe mixture was heated
  2. temperatureat reflux for 12 hours
  3. customThe aqueous layer of the crude mixture was removed
  4. additionthe organic layer was diluted with Et2O (200 ml)
  5. washwashed with 1N NaOH (2×150 ml)
  6. dry with materialwas dried (MgSO2)
  7. filtrationfiltered
  8. customthe soluent was evaporated
  9. customThe residue was chromatographed

Sources & evidence

ORD record
ord-fb2eb4f75d1b4d8894199101e21304dc
Source dataset
uspto-grants-1996_11
Patent number
US05571821

Reaction notes

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