Iodine → 2-(4-Chlorophenyl)-1-(2,4-dichlorophenyl)ethan-1-one

HRID 1392359Notes

Reaction equation

HRID 1392359 reaction equation
[Mg].II.[Cl:4][C:5]1[CH:12]=[CH:11][C:8]([CH2:9]Cl)=[CH:7][CH:6]=1.[Cl:13][C:14]1[CH:21]=[C:20]([Cl:22])[CH:19]=[CH:18][C:15]=1[C:16]#N.C([O:25]CC)C>C1(C)C=CC=CC=1.ClCCl>[Cl:4][C:5]1[CH:12]=[CH:11][C:8]([CH2:9][C:16]([C:15]2[CH:18]=[CH:19][C:20]([Cl:22])=[CH:21][C:14]=2[Cl:13])=[O:25])=[CH:7][CH:6]=1

Participants

8

Reactant 5

HCID 807IodineHCID 3283Diethyl Ether2×HCID 77231-Chloro-4-(chloromethyl)benzeneHCID 810502,4-DichlorobenzonitrileHCID 5462224Magnesium

Product 1

HCID 219848672-(4-Chlorophenyl)-1-(2,4-dichlorophenyl)ethan-1-oneYield 67%

Reagents, catalysts & solvents 2

HCID 1140TolueneSolventHCID 6344DichloromethaneSolvent

Conditions

Temperature
135 °C

Procedure

Part A: Magnesium (3.04 gram, 0.125 mol) is suspended in anhydrous diethyl ether (500 mL) under a nitrogen atmosphere and an iodine crystal is added. A solution of 4-chlorobenzyl chloride (20.12 gram, 0.125 mol) in anhydrous diethyl ether (100 mL) is slowly added to maintain a gentle reflux. After cooling the resulting mixture to room temperature a solution of 2,4-dichlorobenzonitrile (17.2 gram, 0.10 mol) in toluene (100 mL) is slowly added. Temperature is raised to 135° C. and the diethyl ether is removed by distillation, toluene is added and the resulting mixture is refluxed for two additional hours. After cooling to room temperature a solution of HCl (1N, 400 mL) is slowly added under cooling and stirring. The resulting mixture is extracted twice with diethyl ether, dried over MgSO4, filtered and concentrated in vacuo. Flash chromatography (dichloromethane) gives 2-(4-chlorophenyl)-1-(2,4-dichlorophenyl)ethanone as a yellow oil (19.96 gram, 67% yield). Crystallisation from cyclohexane gives pure 2-(4-chlorophenyl)-1-(2,4-dichlorophenyl)ethanone. Melting point: 65-66° C. 1H-NMR (200 MHz, CDCl3): δ 7.02-7.45 (m, 7H), 4.22 (s, 2H).

Workup

  1. temperatureto maintain a gentle reflux
  2. additionis slowly added
  3. customthe diethyl ether is removed by distillation, toluene
  4. additionis added
  5. temperaturethe resulting mixture is refluxed for two additional hours
  6. temperatureAfter cooling to room temperature a solution of HCl (1N, 400 mL)
  7. additionis slowly added
  8. temperatureunder cooling
  9. extractionThe resulting mixture is extracted twice with diethyl ether
  10. dry with materialdried over MgSO4
  11. filtrationfiltered
  12. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-d10be916ab3140febd1283be0d1b7a82
Source dataset
uspto-grants-2008_03
Patent number
US07342032B2

Reaction notes

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