Indole is one of the most important heterocycles in organic synthesis, natural products, and drug discovery. Recently, tremendous advances in the selective functionalization of indoles have been reported. Although the most important advances have been powered by transition metal catalysis, exceedingly useful methods in the absence of transition metals have also been reported. In this review, we provide an overview of functionalization reactions of indoles that have been published in the last years with a focus on the most recent advances, aims, and future trends. The review is organized by the positional selectivity and type of methods used for functionalization. In particular, we discuss major advances in transition‐metal‐catalyzed C−H functionalization at the classical C2/C3 positions, transition‐metal‐catalyzed C−H functionalization at the remote C4/C7 positions, transition‐metal‐catalyzed cross‐coupling, and transition‐metal‐free functionalization.
Total synthesis is considered by many as the finest combination of art and science. During the last decades, several concepts were proposed for achieving the perfect vision of total synthesis, such as atom economy, step economy, or redox economy. In this context, C−H functionalization represents the most powerful platform that has emerged in the last years, empowering rapid synthesis of complex natural products and enabling diversification of bioactive scaffolds based on natural product architectures. In this review, we present an overview of the recent strategies towards the total synthesis of heterocyclic natural products enabled by C−H functionalization. Heterocycles represent the most common motifs in drug discovery and marketed drugs. The implementation of C−H functionalization of heterocycles enables novel tactics in the construction of core architectures, but also changes the logic design of retrosynthetic strategies and permits access to natural product scaffolds with novel and enhanced biological activities.
more » « less- Award ID(s):
- 1650766
- NSF-PAR ID:
- 10445863
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 28
- Issue:
- 22
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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