p-Toluenesulfonic acid → Methyl 3-bromo-2-fluorobenzoate

HRID 396254

Reaction equation

HRID 396254 reaction equation
[Br:1][C:2]1[C:3]([F:11])=[C:4]([CH:8]=[CH:9][CH:10]=1)[C:5]([OH:7])=[O:6].[CH3:12]OC(OC)OC.C1(C)C=CC(S(O)(=O)=O)=CC=1>CO>[Br:1][C:2]1[C:3]([F:11])=[C:4]([CH:8]=[CH:9][CH:10]=1)[C:5]([O:7][CH3:12])=[O:6]

Participants

5

Reactant 3

HCID 6101p-Toluenesulfonic acidHCID 9005Trimethyl orthoformateHCID 27363133-Bromo-2-fluorobenzoic acid

Product 1

HCID 21584505Methyl 3-bromo-2-fluorobenzoateYield 84%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of 3-bromo-2-fluorobenzoic acid (0.219 g, 1 mmol) in dry methanol (5 ml) under nitrogen was treated with trimethylorthoformate (0.22 ml, 2 mmol) and p-toluenesulfonic acid (catalytic amount), and then heated under reflux. After 16 h, the mixture was evaporated and the residue partitioned between water and Et2O. The organic layer was washed with sat. sodium hydrogen carbonate solution, water, brine, dried (MgSO4) and evaporated to give methyl 3-bromo-2-fluorobenzoate (0.195 g, 0.84 mmol, 84%): 1H NMR (CDCl3) δ 7.90-7.85 (m, 1H), 7.71-7.65 (m, 1H), 7.10 (dt, 1H, J=8.0, 1.0 Hz) and 3.94 (s, 3H): MS (EI) 232 (M+).

Workup

  1. temperatureheated
  2. temperatureunder reflux
  3. customthe mixture was evaporated
  4. customthe residue partitioned between water and Et2O
  5. washThe organic layer was washed with sat. sodium hydrogen carbonate solution, water, brine
  6. dry with materialdried (MgSO4)
  7. customevaporated

Sources & evidence

ORD record
ord-b869d62123134d748551ba83a5ee06ab
Source dataset
uspto-grants-2003_08
Patent number
US06608068B2

Linked notes

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