Trifluoroacetic acid → 3-Bromo-6-chloroimidazo(1,2-b)pyridazine

HRID 1959617Notes

Reaction equation

HRID 1959617 reaction equation
[Cl:1][C:2]1[CH:3]=[CH:4][C:5]2[N:6]([CH:8]=[CH:9][N:10]=2)[N:7]=1.C1C(=O)N([Br:18])C(=O)C1.C(O)(C(F)(F)F)=O>C(#N)C>[Br:18][C:8]1[N:6]2[N:7]=[C:2]([Cl:1])[CH:3]=[CH:4][C:5]2=[N:10][CH:9]=1

Participants

5

Reactant 3

HCID 6422Trifluoroacetic acidHCID 67184N-bromobutanimideHCID 138828Imidazo(1,2-b)pyridazine, 6-chloro-

Product 1

HCID 128723233-Bromo-6-chloroimidazo(1,2-b)pyridazineYield 95%

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

To a solution of 6-chloroimidazo[1,2-b]pyridazine (5 g, 32.6 mmol) in acetonitrile (300 mL) was added NBS (6.37 g, 35.8 mmol) and TFA (0.75 mL). The resulting solution was allowed to stir at it overnight. The solvents were removed under reduced pressure and the residue was dissolved in EtOAc, washed with NaHCO3 solution, water and brine, dried over Na2SO4 and concentrated in vacuo to afford 7.2 g (92%) of the title compound as a light yellow solid. 1H-NMR (400 MHz, CDCl3) ppm 7.91 (d, 1H), 7.79 (s, 1H), 7.12 (d, 1H). LCMS (method A): [MH]+=232/234, tR=4.48 min.

Workup

  1. customThe solvents were removed under reduced pressure
  2. dissolutionthe residue was dissolved in EtOAc
  3. washwashed with NaHCO3 solution, water and brine
  4. dry with materialdried over Na2SO4
  5. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-291f5185ad97497bb253e9076861c526
Source dataset
uspto-grants-2013_04
Patent number
US08410264B2

Reaction notes

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