1. C–H Alkylation via Multisite-Proton-Coupled Electron Transfer of an Aliphatic C–H Bond
- Author
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UCL - SST/IMCN/MOST - Molecular Chemistry, Materials and Catalysis, Morton, Carla M., Zhu, Qilei, Ripberger, Hunter, Troian-Gautier, Ludovic, Toa, Zi S. D., Knowles, Robert R., Alexanian, Erik J., UCL - SST/IMCN/MOST - Molecular Chemistry, Materials and Catalysis, Morton, Carla M., Zhu, Qilei, Ripberger, Hunter, Troian-Gautier, Ludovic, Toa, Zi S. D., Knowles, Robert R., and Alexanian, Erik J.
- Abstract
The direct, site-selective alkylation of unactivated C(sp3)–H bonds in organic substrates is a long-standing goal in synthetic chemistry. General approaches to the activation of strong C–H bonds include radical-mediated processes involving highly reactive intermediates, such as heteroatom-centered radicals. Herein, we describe a catalytic, intermolecular C–H alkylation that circumvents such reactive species via a new elementary step for C–H cleavage involving multisite-proton-coupled electron transfer (multisite-PCET). Mechanistic studies indicate that the reaction is catalyzed by a noncovalent complex formed between an iridium(III) photocatalyst and a monobasic phosphate base. The C–H alkylation proceeds efficiently using diverse hydrocarbons and complex molecules as the limiting reagent and represents a new approach to the catalytic functionalization of unactivated C(sp3)–H bonds.
- Published
- 2019