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Synlett
DOI: 10.1055/a-2774-2259
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Published as part of the Special Issue dedicated to Prof. S. Chandrasekaran on his 80th birthday

Benzylic C(sp3)–H Functionalization by Photo Redox Catalysis

Authors

  • Kumari Swati Sharma

    1   Department of Chemistry, Banaras Hindu University, Varanasi, India (Ringgold ID: RIN30114)

  • Sushil Kumar Ranjan

    1   Department of Chemistry, Banaras Hindu University, Varanasi, India (Ringgold ID: RIN30114)

  • Ganesh Pandey 

    1   Department of Chemistry, Banaras Hindu University, Varanasi, India (Ringgold ID: RIN30114)

G. P. thanks SERB, New Delhi, for the award of the National Science Chair (NSC/2021/000024). K. S. S. thanks the University Grants Commission (UGC-JRF), New Delhi, for the research fellowship. S.K.R, thanks for (UGC-NFSC), the authors are also grateful to the BHU and SATHI-BHU for their analytical support.
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Graphical Abstract

Abstract

Benzylic C–H bonds, due to their enhanced reactivity, offer a valuable platform for the selective functionalization in organic synthesis. Recent advancements in catalytic methods have enabled direct transformation of these sp3-hybridized sites under mild conditions. Transition-metal catalysis, photo redox strategies, and radical pathways have shown particular promise. These approaches allow for the construction of diverse C–C and C–X (X = N, O, Br, S) bonds. The presence of electron-withdrawing groups on the substrates significantly reduces the reaction efficiency, representing a limitation of these methodologies. The ability to functionalize benzylic positions through intermolecular and intramolecular methods expand the toolbox for late-stage modification of complex molecules. Such transformations are increasingly important in pharmaceutical and materials chemistry.

Keywords

Benzylic - Intramolecular - Intermolecular - Ffunctionalization - Photo redox catalysis


Publication History

Received: 24 September 2025

Accepted after revision: 10 December 2025

Article published online:
15 January 2026

© 2026. Thieme. All rights reserved.

Georg Thieme Verlag KG
Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

 

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