Azobisisobutyronitrile → Methyl 3-(bromomethyl)-5-tert-butylthiophene-2-carboxylate

HRID 872173Notes

Reaction equation

HRID 872173 reaction equation
[Br:1]N1C(=O)CCC1=O.[C:9]([C:13]1[S:17][C:16]([C:18]([O:20][CH3:21])=[O:19])=[C:15]([CH3:22])[CH:14]=1)([CH3:12])([CH3:11])[CH3:10].CC(N=NC(C#N)(C)C)(C#N)C>C(Cl)(Cl)(Cl)Cl>[Br:1][CH2:22][C:15]1[CH:14]=[C:13]([C:9]([CH3:12])([CH3:11])[CH3:10])[S:17][C:16]=1[C:18]([O:20][CH3:21])=[O:19]

Participants

5

Reactant 3

HCID 6547AzobisisobutyronitrileHCID 67184N-bromobutanimideHCID 57839349Methyl 5-(tert-butyl)-3-methylthiophene-2-carboxylate

Product 1

HCID 66610052Methyl 3-(bromomethyl)-5-tert-butylthiophene-2-carboxylateYield 42%

Reagents, catalysts & solvents 1

HCID 5943Carbon TetrachlorideSolvent

Procedure

N-bromosuccinimide (18.5 g, 0.103 mol) was added to a solution of methyl 5-tert-butyl-3-methylthiophene-2-carboxylate (109b) (20 g, 0.09 mol) and AIBN (0.774 g, 0.0047 mol) in CCl4 (200 mL). The mixture was refluxed for 2 h, cooled to room temperature and filtered. The filtrate was concentrated under vacuum and the obtained residue was purified by flash column chromatography (silica, 95:5 hexanes-/dichloromethane) to afford methyl 3-(bromomethyl)-5-tert-butylthiophene-2-carboxylate (109c) (11 g, 40%) as a pale yellow liquid.

Workup

  1. temperatureThe mixture was refluxed for 2 h
  2. filtrationfiltered
  3. concentrationThe filtrate was concentrated under vacuum
  4. customthe obtained residue was purified by flash column chromatography (silica, 95:5 hexanes-/dichloromethane)

Sources & evidence

ORD record
ord-d85aa1c8d17540d7b2009f07d7a8be2d
Source dataset
uspto-grants-2015_03
Patent number
US08975260B2

Reaction notes

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