Synlett
DOI: 10.1055/a-2705-9302
Letter

Visible-Light-Induced Ru-Catalyzed Ortho C−H Diarylation of 2-Phenyl-2H-Indazoles and 1-Phenyl-1H-Pyrazoles

Authors

  • Sumit Ghosh

    1   Integrated Science Education & Research Centre, Visva-Bharati University, Bolpur, India
  • Asim Kumar Ghosh

    2   Chemistry, Visva-Bharati University, Bolpur, India
  • Frenki Mahato

    2   Chemistry, Visva-Bharati University, Bolpur, India
  • Abu Taher

    3   Chemistry, Bankura University, Bankura, India (Ringgold ID: RIN527357)
  • Subrata Sinha

    1   Integrated Science Education & Research Centre, Visva-Bharati University, Bolpur, India
  • Alakananda Hajra

    2   Chemistry, Visva-Bharati University, Bolpur, India

Supported by: Anusandhan National Research Foundation TAR/2022/000548
Preview

C–H Functionalization is unlocking new avenues in molecular design by transforming the inert carbon-hydrogen bond into a versatile handle for creating complex and value-added compounds with remarkable precision. Taking this into account, we have developed a new ruthenium-catalyzed mild, one-step, robust methodology for ortho C−H diarylation of 2-phenyl-2H-indazoles using aryl iodides as an arylating reagent under photo-mediated conditions at room temperature. This approach extends seamlessly to another heteroarene, 1-phenyl-1H-pyrazole. The strategy shows broad substrate scope, an extensive range of functional group compatibility, and moderate to excellent yield formation. Furthermore, gram-scale synthesis demonstrates the practical applicability of the method.



Publication History

Received: 27 July 2025

Accepted after revision: 01 September 2025

Accepted Manuscript online:
19 September 2025

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