Phosphorus oxychloride → 4-Chloromethyl-2-cyclohexyl-5-methyl-oxazole

HRID 2215204Notes

Reaction equation

HRID 2215204 reaction equation
[CH:1]1([C:7]2[O:8][C:9]([CH3:14])=[C:10]([CH3:13])[N+:11]=2[O-])[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1.O=P(Cl)(Cl)[Cl:17]>C(Cl)Cl>[Cl:17][CH2:13][C:10]1[N:11]=[C:7]([CH:1]2[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]2)[O:8][C:9]=1[CH3:14]

Participants

4

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 219496082-Cyclohexyl-4,5-dimethyl-oxazole 3-oxide

Product 1

HCID 219495724-Chloromethyl-2-cyclohexyl-5-methyl-oxazole

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

25.1 g of the above prepared 2-cyclohexyl-4,5-dimethyl-oxazole 3-oxide (˜88.8 mmol) was dissolved in 325 ml of CH2Cl2 and treated dropwise with 9.755 ml of POCl3 (1.2 eq.). The reaction mixture was refluxed over night and then quenched by carefully pouring onto crashed ice/3N NaOH. Separation of the layers, additional extraction of the aqueous phase with CH2Cl2, washing with Na2CO3 and water, drying of the combined organic phase over sodium sulfate, evaporation of the solvents, and, finally, flash chromatography (SiO2, hexane/AcOEt=9/1) afforded 4.12 g of the title compound as yellowish oil, exhibiting in the 1H-NMR the typical signal at 4.46 ppm (2H). The other, unstable regioisomer was not isolated.

Workup

  1. temperatureThe reaction mixture was refluxed over night
  2. customquenched
  3. additionby carefully pouring
  4. customSeparation of the layers, additional extraction of the aqueous phase with CH2Cl2
  5. washwashing with Na2CO3 and water
  6. dry with materialdrying of the combined organic phase over sodium sulfate, evaporation of the solvents

Sources & evidence

ORD record
ord-0fca3a66359c4f6db3781b00464ce35d
Source dataset
uspto-grants-2006_09
Patent number
US07109225B2

Reaction notes

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