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Updated: Sep 10, 2025
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Coinage Metal-Catalyzed Divergent Heterocyclizations of Underexplored N-Propargyl Hydrazides
Daniel Diez-Iriepa1, Mireia Toledano-Pinedo2, Lorena Herrera-Hernández2
1Department of Chemistry, College of Science, United Arab Emirates University, Al Ain 15551, United Arab Emirates.
Abstract:
Herein, we disclose metal-catalyzed tunable annulations of uncharted alkyne-tethered hydrazides for the divergent preparation of diazacyclic frameworks. Cationic gold facilitates the O-cyclization, providing valuable [1,3,4]oxadiazine scaffolds with total selectivity, whereas silver catalysis promotes controlled N-cyclization to access N-acyl pyrazoles. Furthermore, density-functional-theory-based theoretical investigations support two different pathways (ionic versus radical) operating in the catalytic heterocyclization reaction of the same N-propargyl hydrazide substrate.
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