Hydrochloric Acid → 2-Bromo-3-chloro-4-trifluoromethoxybenzoic acid

HRID 430435Notes

Reaction equation

HRID 430435 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][C:10]=1[O:11][C:12]([F:15])([F:14])[F:13])[C:5]([OH:7])=[O:6].C([Li])CCC.[Br:21]C(Cl)(Cl)C(Cl)(Cl)Br.Cl>O1CCCC1>[Br:21][C:3]1[C:2]([Cl:1])=[C:10]([O:11][C:12]([F:13])([F:14])[F:15])[CH:9]=[CH:8][C:4]=1[C:5]([OH:7])=[O:6]

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 694261,2-Dibromo-1,1,2,2-tetrachloroethaneHCID 27738453-Chloro-4-(trifluoromethoxy)benzoic acidHCID 178418339Butyllithium

Product 1

HCID 183504522-Bromo-3-chloro-4-trifluoromethoxybenzoic acidYield 99.8%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

A solution of 3-chloro-4-trifluoromethoxybenzoic acid (4.15 g) in dry tetrahydrofuran was treated with n-butyl lithium (15.1 ml of 2.5M solution in hexanes) at −78° C. under an inert atmosphere. After stirring overnight at this temperature, a solution of 1,2-dibromotetrachloroethane (839 g) in tetrahydrofuran was added. After 30 minutes, the solution was allowed to slowly warm to ambient temperature, then treated with 2M hydrochloric acid. The mixture was extracted with ether, the ethereal solution itself extracted with sodium bicarbonate solution and the latter acidified with dilute hydrochloric acid. This solution was extracted with ether and evaporated in vacuo to give 2-bromo-3-chloro-4-trifluoromethoxybenzoic acid (5.5 g) as a brown solid, NMR (CDCl3) 7.3(m,1H), 7.8(d,1H).

Workup

  1. waitAfter 30 minutes
  2. extractionThe mixture was extracted with ether
  3. extractionthe ethereal solution itself extracted with sodium bicarbonate solution
  4. extractionThis solution was extracted with ether
  5. customevaporated in vacuo

Sources & evidence

ORD record
ord-9f683cae53c04686a18d115007f88d07
Source dataset
uspto-grants-2001_11
Patent number
US06323155B1

Reaction notes

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