A ligand-free, palladium-catalyzed aminoarylation reaction of the unactivated alkenes in β,γ-unsaturated hydrazones is described. This protocol enables efficient and simultaneous formation of C(sp)-N and C(sp)-C(sp) bonds under mild conditions, providing a practical and general approach to various diversely substituted dihydropyrazoles in generally good yields, without the use of any stoichiometric external oxidant.
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