Herein, we describe a 1,3‐dipolar (3 + 2) cycloaddition between hydrazonoyl chlorides and substituted trifluoromethyl pyrazolones for the synthesis of spirotrifluoromethyl pyrazolone–pyrazole derivatives under transition‐metal‐free conditions. This protocol delivers CF 3 ‐containing pyrazolone frameworks of notable synthetic and biological relevance. The cycloaddition enables the simultaneous formation of new CN and CC bonds, providing the desired spiro products in high yields. Moreover, the reaction demonstrates broad substrate compatibility, underscoring its practicality and synthetic utility.
Eeda et al. (Mon,) studied this question.