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Updated: Aug 16, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Rh2(II)-Catalyzed Enyne Cycloisomerization toward 6-6-5 Tricycles
Haoran Zhang1, Fangyan Liu1, Quan Qian1
1State Key Laboratory of Bio-based Fiber Materials, School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou310018, P. R. China.
Abstract:
A dirhodium-catalyzed diastereoselective cycloisomerization of enynes derived from cyclohexadienone-tethered ynals is described. This reaction enables a concise synthetic pathway toward a library of 6-6-5 fused tricyclic frameworks incorporating three consecutive stereogenic centers. This protocol features excellent diastereoselectivities. Mechanistic studies indicate a dirhodium carbene is possibly involved. Trapping this species with external alkenes furnishes structurally intricate fused/spirocyclic adducts bearing five stereocenters with complete diastereoselectivity.
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