Isothiazoles represent an important class of five‐membered sulfur heterocycles that are widely utilized in medicinal chemistry and organic synthesis due to the unique properties of two electronegative heteroatoms in a 1,2‐relationship. However, in contrast to other 1,2‐azoles, the facile assembly of isothiazoles has always been considered a substantial challenge. In the last decade, major advances have taken place in the fields of synthesis and functionalization of isothiazoles that make them accessible to a wide range of interested chemists through unprecedented pathways. New condensation methods have emerged that address the challenges posed by unstable thiohydroxylamine. New metal‐catalyzed approaches have been reported that deliver densely decorated isothiazoles bearing various sensitive functional groups. New functionalization strategies have been developed through both cross‐coupling and direct C−H activation chemistry. Finally, the emergence of novel heterocyclic architectures based on isothiazole opens the door for future investigations of this versatile heterocyclic scaffold. This review covers the period from January 2004 to December 2018 and is intended as a sequel to the review on isoxazoles, which represent another class of synthetically‐important 1,2‐azoles (see
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.
- Award ID(s):
- 1650766
- NSF-PAR ID:
- 10223962
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Synthesis & Catalysis
- Volume:
- 363
- Issue:
- 11
- ISSN:
- 1615-4150
- Page Range / eLocation ID:
- p. 2723-2739
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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