Switching on elusive organometallic mechanisms with photoredox catalysis

Terrett, Jack A.; Cuthbertson, James; Shurtleff, Valerie W.; MacMillan, David W.C.

Abstract

Transition-metal-catalysed cross-coupling reactions have become one of the most used carbon–carbon and carbon–heteroatom bond-forming reactions in chemical synthesis. Recently, nickel catalysis has been shown to participate in a wide variety of C−C bond-forming reactions, most notably Negishi, Suzuki–Miyaura, Stille, Kumada and Hiyama couplings1,2. Despite the tremendous advances in C−C fragment couplings, the ability to forge C−O bonds in a general fashion via nickel catalysis has been largely unsuccessful. The challenge for nickel-mediated alcohol couplings has been the mechanistic requirement for the critical C–O bond-forming step (formally known as the reductive elimination step) to occur via a Ni(iii) alkoxide intermediate. Here we demonstrate that visible-light-excited photoredox catalysts can modulate the preferred oxidation states of nickel alkoxides in an operative catalytic cycle, thereby providing transient access to Ni(iii) species that readily participate in reductive elimination. Using this synergistic merger of photoredox and nickel catalysis, we have developed a highly efficient and general carbon–oxygen coupling reaction using abundant alcohols and aryl bromides. More notably, we have developed a general strategy to ‘switch on’ important yet elusive organometallic mechanisms via oxidation state modulations using only weak light and single-electron-transfer catalysts.

Citation

Terrett, J. A., Cuthbertson, J., Shurtleff, V. W., & MacMillan, D. W. (2015). Switching on elusive organometallic mechanisms with photoredox catalysis. Nature, 524(7565), 330-334. doi:10.1038/nature14875

• Journal Article Type: Article
• Acceptance Date: Jun 22, 2015
• Publication Date: Aug 12, 2015
• Deposit Date: Jan 22, 2018
• Print ISSN: 0028-0836
• Electronic ISSN: 1476-4687
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 524
• Issue: 7565
• Pages: 330-334
• DOI: https://doi.org/10.1038/nature14875
• Public URL: https://nottingham-repository.worktribe.com/output/1124733
• Publisher URL: https://www.nature.com/articles/nature14875
• Related Public URLs: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4545738/
• PMID: 00035971