1,3-Dipolar cycloaddn. of CH2=CHNO2 to 3-Me, 4-Br, 3-Br and 4-NO2-substituted (Z)-C-phenyl-N-arylnitrones in 1-butyl-3-methylimidazolium chloride at room temperature gave mixts. of 3,4-cis and 3,4-trans-2-aryl-3-phenyl-4-nitro-tetrahydro-1,2-oxazoles in yields 80-85%. The structure of the oxazoles was confirmed by elementary anal. as well as (HNMR)-H-1 and IR spectroscopies.