Practical Access to Fused Carbazoles via Oxidative Benzannulation and their Photophysical Properties
Shweta Rai1,2, Basavarajagouda E Patil1, Priti Kumari3
1Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India.
Abstract:
An aryne annulation strategy for the synthesis of fused carbazoles is developed using indolyl β-ketonitrile in a cascade manner. The reaction sequence involves aryne-mediated [2 + 2] cycloaddition cleavage and intramolecular Michael addition, followed by oxidation under transition-metal-free reaction conditions. Subsequently, conversion of benzo[b]carbazole-6-carbonitrile to carbazole quinone is observed upon prolongation of the reaction time. Furthermore, these materials exhibit high quantum efficiency, which promotes the light-emitting diode applications.
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