Harnessing Rhodium-Catalyzed C-H Activation: Regioselective Cascade Annulation for Fused Polyheterocycles
Maneesh Kumar Reddy Singam1,2, Undamatla Suri Babu1,2, Attunuri Nagireddy1,2
1Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India.
Abstract:
In the realm of transition-metal catalyzed arene functionalization, rhodium(III) catalysis is considered as exemplary due to its propensity to activate C-H bonds to obtain comprehensive molecular assembly. Herein, we demonstrate a new rhodium(III) catalyzed assembly of polyheterocyclic scaffolds via C-H activation and regioselective annulation of 4-arylbut-3-yn-1-amines with 4-hydroxy-2-alkynoates. Heterocyclization and trans-metalation prior to annulation is the key for initiation of this relay redox-neutral catalytic cascade.
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