Acetic Anhydride → 1-(5-Bromo-4-fluoroindazol-1-yl)ethanone

HRID 2400942Notes

Reaction equation

HRID 2400942 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([NH:8][C:9](=[O:11])[CH3:10])=[C:4]([CH3:12])[C:3]=1[F:13].C(OC(=O)C)(=O)C.C([O-])(=O)C.[K+].C1OCCOCCOCCOCCOCCOC1.[N:44](OCCC(C)C)=O>ClCCCl>[Br:1][C:2]1[C:3]([F:13])=[C:4]2[C:5](=[CH:6][CH:7]=1)[N:8]([C:9](=[O:11])[CH3:10])[N:44]=[CH:12]2

Participants

7

Reactant 5

HCID 7918Acetic AnhydrideHCID 8053Isoamyl NitriteHCID 2855718-Crown-6HCID 517044Potassium AcetateHCID 67123438N-(4-Bromo-3-fluoro-2-methylphenyl)acetamide

Product 1

HCID 671234961-(5-Bromo-4-fluoroindazol-1-yl)ethanone

Reagents, catalysts & solvents 1

HCID 111,2-DichloroethaneSolvent

Conditions

Temperature
65 °C

Procedure

N-(4-Bromo-3-fluoro-2-methylphenyl)acetamide (36 mmol) was suspended in 1,2 dichloroethane (150 mL) and acetic anhydride (108 mmol), potassium acetate (74 mmol), 18-Crown-6 (1.4 mmol) and isopentyl nitrite (79 mmol) were added sequentially. The mixture was heated at 65° C. for 24 h, cooled to rt and washed with sat. NaHCO3. The organic layer was dried (Na2SO4) and concentrated and the residue was purified by flash chromatography (0-20% EtOAc/hexanes). 1-(5-Bromo-4-fluoroindazol-1-yl)ethanone was obtained as a brown solid.

Workup

  1. temperaturecooled to rt
  2. washwashed with sat. NaHCO3
  3. dry with materialThe organic layer was dried (Na2SO4)
  4. concentrationconcentrated
  5. customthe residue was purified by flash chromatography (0-20% EtOAc/hexanes)

Sources & evidence

ORD record
ord-8abd23e0bbd14ffaa927ae166b7db053
Source dataset
uspto-grants-2014_08
Patent number
US08796256B2

Reaction notes

Loading…