Abstract
Phthalimide-N-oxyl (PINO) is a valuable hydrogen-atom-transfer (HAT) catalyst for selective C–H functionalization. To advance and optimize PINO-catalysed HAT reactions, researchers have been focused on modifying the phthalimide core structure. Despite much effort and some notable advances, the modifications to date have centred on optimization of a single parameter of the catalyst, such as reactivity, solubility or stability. Unfortunately, the optimization with respect to one parameter is often associated with a worsening of the others. The derivation of a single catalyst structure with optimal performance across multiple parameters has therefore remained elusive. Here we present an analysis of the structure–activity relationships of PINO and its derivatives as HAT catalysts, which we hope will stimulate further development of PINO-catalysed HAT reactions and, ultimately, lead to much improved catalysts for real-world applications.
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Acknowledgements
C.R.J.S. and S.M. acknowledge the financial support from the National Science Foundation (CBET-2033714), and the University of Michigan. D.A.P. acknowledges the financial support from the Natural Sciences and Engineering Research Council of Canada (RGPIN-2022-05058). C.Y. acknowledges a Rackham pre-doctoral fellowship from the University of Michigan.
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C.Y., S.M., D.A.P. and C.R.J.S. contemplated the topic and structure of the Review. C.Y. conducted the literature research. All authors contributed to the discussion of the content and wrote or edited the manuscript.
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Yang, C., Arora, S., Maldonado, S. et al. The design of PINO-like hydrogen-atom-transfer catalysts. Nat Rev Chem 7, 653–666 (2023). https://doi.org/10.1038/s41570-023-00511-z
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DOI: https://doi.org/10.1038/s41570-023-00511-z
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