Palladium-Catalyzed Cascade Cyclization/Alkynylation Reactions
Jianxiao Li1, Shaorong Yang1, Wanqing Wu1
1Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China.
Abstract:
Palladium-catalyzed cascade cyclization reactions have witnessed significant improvements in recent years. Among them, palladium-catalyzed cascade cyclization/alkynylation are especially attractive, which can assemble structurally diverse monocyclic, bicyclic, fused polycyclic, and spirocyclic skeletons with excellent chemoselectivities. In this Minireview, palladium-catalyzed cascade cyclization/alkynylation have been summarized and discussed in detail with focus on oxypalladation and aminopalladation-initiated cascade cyclization, intramolecular Heck-type cascade cyclization, carbocyclizations, cascade cyclizations, and other types of cascade cyclization reactions. Some significant and representative synthetic methodologies and their synthetic applications and reaction mechanisms have also been described.
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