Azobisisobutyronitrile → Methyl 4'-(bromomethyl)biphenyl-2-carboxylate
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]=1Participants
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
- temperatureat reflux under nitrogen for 24 hours
- temperatureat reflux for an additional 24 hours
- filtrationThe reaction was filtered
- customthe solvent removed in in vacuo
- customPurification by silica gel chromatography (Waters Prep-500A)
Sources & evidence
- ORD record
- ord-85a442a6c27048508e57e97a15caefa1
- Source dataset
- uspto-grants-1992_03
- Patent number
- US05098920
Reaction notes
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