Assembly of 1,3-Diaryl-1H-pyrazoles via Base-Mediated [3+2] cycloaddition
Abstract
1,3-Diaryl-1H-pyrazoles, serving as privileged heterocyclic scaffolds, demonstrate significant application potential in pharmaceutical development, functional materials, and agrochemical industries. This study presents a synthetic strategy based on [3+2] cycloaddition, achieving efficient construction of 1,3-Diaryl-1H-pyrazoles. A novel transition metal-free protocol was established through base-catalyzed intermolecular annulation of hydrazone with vinyl sulfoxides, followed by oxidation. The reaction system exhibited excellent substrate generality and demonstrated successful gram-scale synthesis. Subsequent investigations into synthetic applications further confirmed the methodology's practicality and scalability.