Palladium-Catalyzed N-Allylic Alkylation of Pyrazoles and Unactivated Vinylcyclopropanes
Shao-Jie Cheng1, Xin-Li Zhang1, Zhen-Xu Yang1
1School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China.
Abstract:
An efficient palladium-catalyzed N-allylic alkylation of pyrazoles and unactivated vinylcyclopropanes is demonstrated, affording various N-alkyl pyrazoles in ≤99% yield. This protocol displays high atom economy, a broad range of substrates, and excellent regioselectivity and stereoselectivity. Late-stage modification of bioactive molecules, scaled-up reaction, and divergent derivatization documented the practicability of this methodology. The preliminary mechanistic investigation hinted that the Pd-H species promotes the ring opening of cyclopropanes.
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