Platinum Iodide-Catalyzed Formal Three-Component Cascade Cycloaddition Reactions between γ-Aminoalkynes and
Xinhong Li1, Chunhui Jiang2, Xiao Wang1
1The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, P. R. China.
Abstract:
Herein, we report a protocol for PtI2-catalyzed formal three-component cascade cycloaddition reactions between γ-aminoalkynes and electron-deficient alkynes to afford highly substituted cyclohexadiene-b-pyrrolidines in good yields. On the basis of the results of the control experiments and density functional theory calculations, we present a plausible mechanism that proceeds via two key intermediates. The overall transformation involves the cleavage and formation of multiple C-C and C-N bonds and a previously unreported reaction mode of a seven-membered nitrogen heterocyclic intermediate.
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