Phosphorus oxybromide → 3-Bromo-6-phenylpyridazine

HRID 2053699Notes

Reaction equation

HRID 2053699 reaction equation
[C:1]1([C:7]2[N:12]=[N:11][C:10](O)=[CH:9][CH:8]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.P(Br)(Br)([Br:16])=O>C1(C)C=CC=CC=1>[Br:16][C:10]1[N:11]=[N:12][C:7]([C:1]2[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=2)=[CH:8][CH:9]=1

Participants

4

Reactant 2

HCID 24613Phosphorus oxybromideHCID 178515859HCID 178515859, compound

Product 1

HCID 111956883-Bromo-6-phenylpyridazineYield 31.8%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
900 °C

Procedure

6-Phenylpyridazin-3-ol (5.0 g, 29.06 mmol) is dissolved in toluene (100 mL) and heated to 900° C. Phosphorous oxybromide (25 g, 87.19 mmol) is added in several portions and the reaction is heated for 30 minutes. The resulting yellow solution is cooled to room temperature, poured onto ice water, and extracted with ethyl acetate. The organic layers are further washed with water and 1M NaOH, dried over MgSO4, filtered, and evaporated to a yellow solid. Recrystallization from CHCl3 gives 2.17 g of 3-bromo-6-phenylpyridazine.

Workup

  1. temperaturethe reaction is heated for 30 minutes
  2. temperatureThe resulting yellow solution is cooled to room temperature
  3. additionpoured onto ice water
  4. extractionextracted with ethyl acetate
  5. washThe organic layers are further washed with water and 1M NaOH
  6. dry with materialdried over MgSO4
  7. filtrationfiltered
  8. customevaporated to a yellow solid
  9. customRecrystallization from CHCl3

Sources & evidence

ORD record
ord-67f11dc6443d42f5876d747f17386511
Source dataset
uspto-grants-2008_02
Patent number
US07326731B2

Reaction notes

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