An efficient way for the synthesis of trifluoromethylpyrroles and related compounds from easily prepared trifluoromethyloxazolone via 1,3-dipolar cycloaddn. and the base promoted cyclocondensation reaction was described. E.g., the 1,3-dipolar cycloaddn. of trifluoromethyloxazolones I (R = Ph, 4-ClC6H4) with di-Me acetylenedicarboxylate gave cycloadducts II, which were transformed into trifluoromethylpyrroles III after decarboxylation. The base promoted cyclocondensation involves the tandem Michael addition of trifluoromethyloxazolones to electron-deficient alkenes, intramol. cyclization and decarboxylation to give trifluoromethylpyrroles in good yield.

Key words: INSECTICIDES, MANNICH REACTION