Dimethylformamide → 3-Bromo-5-fluorobenzaldehyde

HRID 1990950Notes

Reaction equation

HRID 1990950 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 min. 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) 6 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. customAfter 30 min. the 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-5d383b95b2a743a599b8e57ff7f12f12
Source dataset
uspto-grants-2010_01
Patent number
US07645761B2

Reaction notes

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