@article{8160be2090614457894fd13cd28892d2,
title = "Radical Redox Annulations: A General Light-Driven Method for the Synthesis of Saturated Heterocycles",
abstract = "We introduce here a two-component annulation strategy that provides access to a diverse collection of five- and six-membered saturated heterocycles from aryl alkenes and a family of redox-active radical precursors bearing tethered nucleophiles. This transformation is mediated by a combination of an Ir(III) photocatalyst and a Br{\o}nsted acid under visible-light irradiation. A reductive proton-coupled electron transfer generates a reactive radical which undergoes addition to an alkene. Then, an oxidative radical-polar crossover step leading to carbocation formation is followed by ring closure through cyclization of the tethered nucleophile. A wide range of heterocycles are easily accessible, including pyrrolidines, piperidines, tetrahydrofurans, morpholines, δ-valerolactones, and dioxanones. We demonstrate the scope of this approach through broad structural variation of both reaction components. This method is amenable to gram-scale preparation and to complex fragment coupling.",
keywords = "PCET, annulation, carbocations, heterocycles, photocatalysis",
author = "Murray, {Philip R.D.} and Leibler, {Isabelle Nathalie Marie} and Hell, {Sandrine M.} and Eris Villalona and Doyle, {Abigail G.} and Knowles, {Robert R.}",
note = "Funding Information: Funding for this work was provided by the NIH (R35 GM134893 to R.R.K.) and the NSF (CHE-2102266 to A.G.D.). P.R.D.M. wishes to thank the European Commission for a Marie-Sk{\l}odowska-Curie Individual Fellowship (grant number: 886224). We thank Nicholas D. Chiappini and Jacob M. Ganley of the Princeton University for helpful discussions. We thank Erik J. Sorensen, Nicholas A. Falcone, and John F. Hoskin of the Princeton University for providing complex diene starting material for annulation example 12 and for helpful discussions. We thank Brandon Kennedy of Lotus separations and Alberto Castanedo of the Princeton University for assistance with the purification of various annulation products. We thank Istv{\'a}n Pelczer and Kenith Conover for assistance with NMR experiments and John Eng for assistance with mass spectrometry. Publisher Copyright: {\textcopyright} 2022 American Chemical Society. All rights reserved.",
year = "2022",
month = nov,
day = "4",
doi = "10.1021/acscatal.2c04316",
language = "English (US)",
volume = "12",
pages = "13732--13740",
journal = "ACS Catalysis",
issn = "2155-5435",
publisher = "American Chemical Society",
number = "21",
}