Azobisisobutyronitrile → Methyl 4'-(bromomethyl)biphenyl-2-carboxylate

HRID 719539Notes

Reaction equation

HRID 719539 reaction equation
[C:1]1([CH3:17])[CH:6]=[CH:5][C:4]([C:7]2[CH:16]=[CH:15][CH:14]=[CH:13][C:8]=2[C:9]([O:11][CH3:12])=[O:10])=[CH:3][CH:2]=1.[Br:18]N1C(=O)CCC1=O.N(C(C)(C)C#N)=NC(C)(C)C#N>C(Cl)(Cl)(Cl)Cl>[Br:18][CH2:17][C:1]1[CH:2]=[CH:3][C:4]([C:7]2[CH:16]=[CH:15][CH:14]=[CH:13][C:8]=2[C:9]([O:11][CH3:12])=[O:10])=[CH:5][CH:6]=1

Participants

5

Reactant 3

HCID 6547Azobisisobutyronitrile2×HCID 67184N-bromobutanimideHCID 1393873(1,1'-Biphenyl)-2-carboxylic acid, 4'-methyl-, methyl ester

Product 1

HCID 11012181Methyl 4'-(bromomethyl)biphenyl-2-carboxylateYield 78%

Reagents, catalysts & solvents 1

HCID 5943Carbon TetrachlorideSolvent

Procedure

A 47.46 g (210 mmol) sample of methyl 2-(p-tolyl)benzoate (Chemo Dynamics Inc.) was dissolved in 3 L of carbon tetrachloride and treated with 37.33 g (209 mmol) of N-bromosuccinimide (NBS) and 1.17 g (7.13 mmol) of azobisisobutyronitrile (AIBN) at reflux under nitrogen for 24 hours. The reaction mixture was treated again with 1.0 g (6.1 mmol) of AIBN and stirred at reflux for an additional 24 hours. The reaction was filtered and the solvent removed in in vacuo. Purification by silica gel chromatography (Waters Prep-500A) using ethyl acetate/hexane (5:95) as eluent provided 50.0 g (78%) of a colorless solid: mp 48–51° C.; NMR (CDCl3) δ 3.64 (s, 3H), 4.54 (s, 2H), 7.23–7.63 (m, 7H), 7.81–7.89 (m, 1H). NMR indicated that this material was only 91% pure; it contained 9% of the corresponding dibromocompound (δ 6.70); however, no further attempts at purification were made and this mixture was used in all subsequent alkylation reactions.

Workup

  1. temperatureat reflux under nitrogen for 24 hours
  2. temperatureat reflux for an additional 24 hours
  3. filtrationThe reaction was filtered
  4. customthe solvent removed in in vacuo
  5. customPurification by silica gel chromatography (Waters Prep-500A)

Sources & evidence

ORD record
ord-71128818a4f744a399ac02562d159ba9
Source dataset
uspto-grants-2006_11
Patent number
US07132437B2

Reaction notes

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