Ethyl Acetate → 2-bromo-1-[1-(propan-2-yl)-1H-1,2,4-triazol-5-yl]ethan-1-one

HRID 1800022Notes

Reaction equation

HRID 1800022 reaction equation
[CH:1]([N:4]1[C:8]([C:9](=[O:11])[CH3:10])=[N:7][CH:6]=[N:5]1)([CH3:3])[CH3:2].[Br-:12].[Br-].[Br-].C1([N+](C)(C)C)C=CC=CC=1.C1([N+](C)(C)C)C=CC=CC=1.C1([N+](C)(C)C)C=CC=CC=1.C(OCC)(=O)C>C(O)(=O)C.C1COCC1.C1CCCCC1>[Br:12][CH2:10][C:9]([C:8]1[N:4]([CH:1]([CH3:3])[CH3:2])[N:5]=[CH:6][N:7]=1)=[O:11]

Participants

7

Conditions

Temperature
75 °C

Procedure

To a solution of 1-(2-isopropyl-2H-[1,2,4]triazol-3-yl)-ethanone (10 g, 65.3 mmol) in acetic acid (1 mL) and THF (100 mL) was added a solution of PTT (phenyltrimethylammonium tribromide, 24.5 g, 65.3 mmol) in THF (100 mL) over 20 min. The reaction mixture was heated at 75° C. before cooling to RT. The resultant mixture was concentrated in vacuo and the products partitioned between ethyl acetate and saturated aqueous sodium bicarbonate solution. The organic layer was separated, dried (Na2SO4), filtered and concentrated in vacuo to give a residue which was subjected to flash chromatography (SiO2, gradient 0 to 20% ethyl acetate in cyclohexane) to give 2-Bromo-1-(2-isopropyl-2H-[1,2,4]triazol-3-yl)-ethanone as an oil (5.4 g, 36%). 1H NMR δ (ppm) (CDCl3): 7.98 (1H, s), 5.53-5.42 (1H, m), 4.69 (2H, s), 1.52 (6H, d, J=6.63 Hz).

Workup

  1. temperaturebefore cooling to RT
  2. concentrationThe resultant mixture was concentrated in vacuo
  3. customthe products partitioned between ethyl acetate and saturated aqueous sodium bicarbonate solution
  4. customThe organic layer was separated
  5. dry with materialdried (Na2SO4)
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo
  8. customto give a residue which

Sources & evidence

ORD record
ord-fb988fc9201b47f996ae06e4bff97949
Source dataset
uspto-grants-2013_01
Patent number
US08343955B2

Reaction notes

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