Boron tribromide → 2-Hydroxy-5-(trifluoromethoxy)benzaldehyde

HRID 965011Notes

Reaction equation

HRID 965011 reaction equation
C[O:2][C:3]1[CH:10]=[CH:9][C:8]([O:11][C:12]([F:15])([F:14])[F:13])=[CH:7][C:4]=1[CH:5]=[O:6].B(Br)(Br)Br.C(=O)=O.CC(C)=O.C(=O)(O)[O-].[Na+]>O.ClCCl>[OH:2][C:3]1[CH:10]=[CH:9][C:8]([O:11][C:12]([F:13])([F:14])[F:15])=[CH:7][C:4]=1[CH:5]=[O:6]

Participants

7

Reactant 4

HCID 25134Boron tribromideHCID 516892Sodium BicarbonateHCID 27833642-Methoxy-5-(trifluoromethoxy)benzaldehydeHCID 18522661Acetone cardice

Product 1

HCID 12680582-Hydroxy-5-(trifluoromethoxy)benzaldehydeYield 69.3%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent

Procedure

Under a nitrogen atmosphere, in a round-bottom flask were placed 300 mg (1.4 mmol) of 2-methoxy-5-trifluoromethoxybenzaldehyde and 30 ml of dichloromethane. To the system, cooled in a dry ice acetone bath, were added 0.26 ml (2.7 mmol) of boron tribromide (BBr3) over a period of ca. 1 minute. The reaction mixture was stirred for 1 hour, the dry ice/acetone bath was replaced with an ice bath and the mixture was stirred for 1 hour. To the system were added slowly 10 ml of saturated aqueous sodium bicarbonate followed by 10 ml of water, and the mixture was warmed to room temperature. The mixture was extracted with two portions of dichloromethane, and the extracts were dried (Na2SO4) and concentrated. The resulting oil (280 mg) was dissolved in CH2 Cl2, and the solution was extracted with two portions of 1M aqueous NaOH. The combined aqueous extracts were acidified with 2M aqueous HCl and extracted with three portions of dichloromethane. These dichloromethane extracts were dried (Na2SO4) and concentrated to obtain 200 mg of the title compound. 1H NMR (CDCl3) Δ 6.96 (d, 1H, J=9), 7.36 (m, 2H), 9.84 (s, 1H), 10.9 (s, 1H).

Workup

  1. customUnder a nitrogen atmosphere, in a round-bottom flask were placed
  2. temperatureTo the system, cooled in a dry ice acetone bath
  3. stirringthe mixture was stirred for 1 hour
  4. extractionThe mixture was extracted with two portions of dichloromethane
  5. dry with materialthe extracts were dried (Na2SO4)
  6. concentrationconcentrated
  7. dissolutionThe resulting oil (280 mg) was dissolved in CH2 Cl2
  8. extractionthe solution was extracted with two portions of 1M aqueous NaOH
  9. extractionextracted with three portions of dichloromethane
  10. dry with materialThese dichloromethane extracts were dried (Na2SO4)
  11. concentrationconcentrated

Sources & evidence

ORD record
ord-f1f5f3a52d4f4954a4c97ccf9dbcc55a
Source dataset
uspto-grants-1998_06
Patent number
US05773450

Reaction notes

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