Ru/O2-Catalyzed Oxidative C-H Activation/Alkyne Annulation Using Quinoline-Functionalized NHC as a Directing and
Monuranjan Konwar1, Nitumoni Hazarika1, Animesh Das1
1Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, Assam India.
Abstract:
The ruthenium/O2-catalyzed oxidative annulation reaction of imidazo[1,5-a]quinolin-2-ium salts with alkynes via N-heterocyclic carbene-directed C-H activation to obtain π-conjugated fused imidazo[1,5-a]quinolin-2-ium derivatives is reported. Molecular oxygen has been explored as an economic and clean oxidant and an alternative to metal oxidants. The current protocol exhibits a wide range of substrate scope including bioactive (±)-α-tocopherol derivatives. Moreover, most of the annulated products show strong fluorescence properties, indicating their potential for making new light-emitting materials.
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