Dimethylformamide → 3-Bromo-5-fluorobenzaldehyde

HRID 990657Notes

Reaction equation

HRID 990657 reaction equation
Br[C:2]1[CH:3]=[C:4]([F:9])[CH:5]=[C:6]([Br:8])[CH:7]=1.C([Li])CCC.CN([CH:18]=[O:19])C>C(OCC)C>[F:9][C:4]1[CH:3]=[C:2]([CH:7]=[C:6]([Br:8])[CH:5]=1)[CH:18]=[O:19]

Participants

5

Reactant 3

HCID 6228DimethylformamideHCID 1370031,3-Dibromo-5-fluorobenzeneHCID 178418339Butyllithium

Product 1

HCID 219862463-Bromo-5-fluorobenzaldehydeYield 100%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent2×

Procedure

To a solution of 3,5-dibromofluorobenzene in diethyl ether (100 cm3) at −78° C. was added n-butyl lithium (2.5 M, 8 cm3, 20 mmol) dropwise. After 30 min. the mixture was treated with DMF (20 cm3) in diethyl ether (10 cm3) and stirring was continued at −78° C. After 30 mnin. the mixture was quenched with dilute HCl aq., separated and the aqueous layer was extracted with EtOAc. The combined organic layers were combined, washed with water, brine, dried (MgSO4) and evaporated to give 3-fluoro-5-bromobenzaldehyde (4.0 g, 19.7 mmol, 100%) as an oil: 1H NMR (CDCl3) δ inter alia 7.50-7.53 (m, 2H), 7.82 (s, 1H) and 9.93 (m, 1H); MS (EI) m/z 202, 204 [M+].

Workup

  1. customwas continued at −78° C
  2. customthe mixture was quenched with dilute HCl aq.
  3. customseparated
  4. extractionthe aqueous layer was extracted with EtOAc
  5. washwashed with water, brine
  6. dry with materialdried (MgSO4)
  7. customevaporated

Sources & evidence

ORD record
ord-807e55eeb2b44f3c9af17f2e07a0b545
Source dataset
uspto-grants-2002_10
Patent number
US06462032B1

Reaction notes

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