Dichloromethane → HCID 21949596, compound

Participants

Reaction Steps

In step b], both products were isolated and characterized as follows: 36.27 g of 2-cyclopropyl-4,5-dimethyl-oxazole 3-oxide (152 mmol, prepared from cyclohexanecarboxaldehyde and diacetyl monooxime as described above) was dissolved in 555 ml of CH2Cl2 and treated dropwise with 16.75 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) yielded in the less polar fractions 6.53 g of 2-(1,3-dichloro-propyl)-4,5-dimethyl-oxazole (MS: 207.1, 209.1 (M+)) and in the more polar ones 10.33 g of 4-chloromethyl-2-cyclopropyl-5-methyl-oxazole as colorless liquid, exhibiting in the 1H-NMR the typical signals at 4.42 ppm (s, 2H), 2.27 (s, 3H), 1.97–2.03 ppm (m, 1H), 0.98–1.04 ppm (m, 4H).

Provenance & Evidence