Boron tribromide → 4-((5-Bromo-2-chlorophenyl)methyl)phenol

HRID 425099Notes

Reaction equation

HRID 425099 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[C:4]([CH2:9][C:10]2[CH:15]=[CH:14][C:13]([O:16]CC)=[CH:12][CH:11]=2)[CH:3]=1.B(Br)(Br)Br>ClCCl>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[C:4]([CH:3]=1)[CH2:9][C:10]1[CH:15]=[CH:14][C:13]([OH:16])=[CH:12][CH:11]=1

Participants

4

Reactant 2

HCID 25134Boron tribromideHCID 99964494-Bromo-1-chloro-2-(4-ethoxy-benzyl)-benzene2×

Product 1

HCID 574237514-((5-Bromo-2-chlorophenyl)methyl)phenolYield 68%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a stirred solution of 4-bromo-1-chloro-2-(4-ethoxybenzyl)benzene (intermediate B) (747 g, 2.31 mol) in dichloromethane was added slowly boron tribromide (1.15 kg, 4.62 mol) at −78° C. The reaction mixture was allowed to warm to room temperature. When the reaction was complete as measured by TLC, the reaction was quenched with water. The mixture was extracted with dichloromethane. The organic layer was washed with an aqueous solution of saturated sodium bicarbonate, then with water, and then with brine, and dried over Na2SO4. The residue was concentrated and then recrystallized in petroleum ether to obtain intermediate H as a white solid (460 g, yield 68%). 1H NMR (CDCl3, 400 MHz): δ 7.23˜7.29 (m, 3H), 7.08 (d, J=8.8 Hz, 2H), 6.79 (d, J=8.8 Hz, 2H), 5.01 (s, 1H), 4.00 (s, 2H).

Workup

  1. customthe reaction was quenched with water
  2. extractionThe mixture was extracted with dichloromethane
  3. washThe organic layer was washed with an aqueous solution of saturated sodium bicarbonate
  4. dry with materialwith water, and then with brine, and dried over Na2SO4
  5. concentrationThe residue was concentrated
  6. customrecrystallized in petroleum ether

Sources & evidence

ORD record
ord-20b9cb8ae6c44dc495e15d26f05129a6
Source dataset
uspto-grants-2012_01
Patent number
US08106021B2

Reaction notes

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