1,2-Diaza-1,3-butadienes react regioselectively with trifluoromethylated β-dicarbonyl compounds to give stable 2-(trifluoromethyl)-2,3-dihydro-1H-pyrrol-2-ol derivatives, which upon treatment with trifluoromethanesulphonic anhydride or with heterogeneous catalysts give rise to fluorinated 1-aminopyrrole derivatives in good to excellent yields. The reaction of 2-(trifluoromethyl)-2,3-dihydro-1H-pyrrol-2-ol derivative with 2-haloketone affords fluorinated furo[2,3-b]pyrroline derivative, while that of diethyl 1-[(anilinocarbonyl)amino]-2-methyl-5-(trifluoromethyl)-1H-pyrrole-3,4-dicarboxylate with hydrazine hydrate affords fluorinated pyrrolo[3,4-d]pyridazindione derivative.
1,2-diaza-1,3-butadienes - Michael additions - regioselectivity - 2-(trifluoromethyl)-2,3-dihydro-1H-pyrrol-2-ols - heterocycles