1,3-Dichloroacetone → 2-tert-Butyl-4-(chloromethyl)-1,3-oxazole

Participants

Reaction Conditions

Reaction Steps

A mixture of pivalamide (30 g) and 1,3-dichloro-2-propanone (37.66 g) was stirred at 160° C. for 1.5 hrs. Saturated aqueous sodium hydrogen carbonate and ethyl acetate were added to the reaction mixture, and insoluble materials were removed by filtration. The organic layer was separated, dried over anhydrous magnesium sulfate and concentrated. The residue was subjected to silica gel column chromatography and eluted with ethyl acetate-hexane (1:5-1:2, v/v). The obtained oily substance (a mixture (41 g) of 2-tert-butyl-4-chloromethyl-1,3-oxazole and 1,3-dichloro-2-propanone) was dissolved in tetrahydrofuran (500 mL) ethanol (50 mL), sodium borohydride (5 g) was added, and the mixture was stirred at room temperature for 16 hrs. Water was poured into the reaction mixture, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was subjected to silica gel column chromatography and eluted with ethyl acetate-hexane (1:20, v/v) to give 2-tert-butyl-4-(chloromethyl)-1,3-oxazole as a colorless oil (19.61 g, yield 38%).

Provenance & Evidence