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Updated: May 20, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Ligand-Controlled Divergent Synthesis of cis/trans-Trisubstituted Cycloalkenes via Pd-Catalyzed [6+4] Cyclization
Bin Shi1, Wei Xiong1, Jin-Pu Zhao1
1Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei, China.
Abstract:
Medium-sized cycloalkenes are pivotal motifs in natural products and bioactive molecules, yet the divergent and stereoselective synthesis of their cis- and trans-isomers remains a long-standing challenge. To address this, we present a ligand-controlled, Pd-catalyzed [6+4] dipolar cyclization between N-PMB vinyl carbamates and azadienes that enables the divergent synthesis of both cis- and trans-trisubstituted 10-membered cycloalkenes. The key to this success is the ligand-modulated stability of the cis- and trans-π-allyl-Pd dipolar intermediates, allowing for high stereoselectivity by a simple switch of the phosphine ligand. This strategy provides a versatile and efficient platform for precisely constructing challenging medium-sized cycloalkenes with controlled olefin geometry.
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