Synthesis of spirocyclopropylpyrazole derivatives via the cascade reaction of alkylidenecyclopropanes with pyrazolidinones and trifluoroethanol

Presented herein is a novel synthesis of spirocyclopropylpyrazoles tethered with a trifluoromethyl unit through an unprecedented cascade reaction of alkylidenecyclopropanes with pyrazolidinones and trifluoroethanol.