Bromine → 2(4-Dibromomethylphenyl)pyridine

HRID 1066403Notes

Reaction equation

HRID 1066403 reaction equation
C1(C)C=CC(C2C=CC=CN=2)=CC=1.O.C1(S(O)(=O)=O)C=CC=CC=1.[Br:25]Br.[Br:27][CH2:28][C:29]1[CH:34]=[CH:33][C:32]([C:35]2[CH:40]=[CH:39][CH:38]=[CH:37][N:36]=2)=[CH:31][CH:30]=1>ClC1C=CC=CC=1.O>[Br:27][CH:28]([Br:25])[C:29]1[CH:30]=[CH:31][C:32]([C:35]2[CH:40]=[CH:39][CH:38]=[CH:37][N:36]=2)=[CH:33][CH:34]=1

Participants

7

Reactant 4

HCID 24408BromineHCID 782192-(p-Tolyl)pyridineHCID 98875912-(4-(Bromomethyl)phenyl)pyridineHCID 15619088Hydroxybenzenesulfonic acid

Product 1

HCID 98266562(4-Dibromomethylphenyl)pyridineYield 68.89%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 7964ChlorobenzeneSolvent

Procedure

In a 300 ml four neck flask equipped with a water separator were placed 2-(4-tolyl)pyridine (20.0 g, 0.118 mol), chlorobenzene (100 ml) and benzenesulfonic acid monohydrate (20.82 g, 0.118 mol), and the mixture was heated. At around 90° C., water was azeotropically distilled into the water separator. The mixture was further heated while distilling water until the temperature of the distillate reached 131° C. Bromine (26.4 g, 0.165 mol) was added dropwise to this reaction mass at 120-130° C. over 8 hours. The reaction mixture was stirred with heating at a temperature in the above-mentioned range for 4 hours and analyzed by HPLC. As a result, 2-(4-bromomethylphenyl)pyridine was confirmed to have been produced in a 68.89% yield and 2-(4-dibromomethylphenyl)pyridine was confirmed to have been produced in a 19.49% yield. This reaction mass was used as it was in the next reaction. From the 1H-NMR analysis, production of 2-(4-bromomethylphenyl)pyridine benzenesulfonate and 2-(4-dibromomethylphenyl)pyridine benzenesulfonate was confirmed.

Workup

  1. temperaturethe mixture was heated
  2. distillationAt around 90° C., water was azeotropically distilled into the water separator
  3. temperatureThe mixture was further heated
  4. distillationwhile distilling water until the temperature of the distillate
  5. customreached 131° C
  6. temperaturewith heating at a temperature in the above-mentioned range for 4 hours

Sources & evidence

ORD record
ord-71205431e06f4282879497560874679c
Source dataset
uspto-grants-2001_06
Patent number
US06242608B1

Reaction notes

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