4-Methylbenzaldehyde → 1-(4-Methylphenyl)-7-chloro-1-hepten-3-one

HRID 67885Notes

Reaction equation

HRID 67885 reaction equation
[Cl-:1].[O:2]1[CH2:7][CH2:6][CH2:5][CH2:4][C:3]1=[CH:8][P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.[CH3:28][C:29]1[CH:36]=[CH:35][C:32]([CH:33]=O)=[CH:31][CH:30]=1>C1(C)C(C)=CC=CC=1>[CH3:28][C:29]1[CH:36]=[CH:35][C:32]([CH:33]=[CH:8][C:3](=[O:2])[CH2:4][CH2:5][CH2:6][CH2:7][Cl:1])=[CH:31][CH:30]=1

Participants

4

Reactant 2

HCID 77254-MethylbenzaldehydeHCID 73680070[(tetrahydro-2H-pyran-2-ylidene)methyl]triphenylphosphonium chloride

Product 1

HCID 541675721-(4-Methylphenyl)-7-chloro-1-hepten-3-one

Reagents, catalysts & solvents 1

HCID 7237O-XyleneSolvent

Procedure

2 parts of [(tetrahydro-2H-pyran-2-ylidene)methyl] triphenylphosphonium chloride and 0.82 part of 4-methylbenzaldehyde were combined in 45 parts of xylene. This suspension was maintained under a nitrogen atmosphere and was refluxed for 4.5 hours to produce a clear solution. After the solution was cooled to room temperature, the xylene was removed at a temperature of about 40° C., under reduced pressure to yield a product mixture. This mixture was separated chromatographically on a silica column using as an elution solvent increasing concentrations of ethyl acetate in toluene, to yield 1-(4-methylphenyl)-7-chloro-1-hepten-3-one in the fraction containing 1.5 percent by volume of ethyl acetate in toluene which, after recrystallization from cyclohexane, melted at about 79°-82° C.

Workup

  1. temperatureThis suspension was maintained under a nitrogen atmosphere
  2. temperaturewas refluxed for 4.5 hours
  3. customto produce a clear solution
  4. customthe xylene was removed at a temperature of about 40° C., under reduced pressure
  5. customto yield a product mixture
  6. customThis mixture was separated chromatographically on a silica column
  7. temperatureincreasing concentrations of ethyl acetate in toluene

Sources & evidence

ORD record
ord-2f9b8dfaf3e9489a8398eb93d704bf98
Source dataset
uspto-grants-1982_08
Patent number
US04347192

Reaction notes

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