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DOE OSTI · 3031159

Light-Promoted C(sp 3 )–C(sp 3 ) Reductive Elimination from Dialkyl NiII Complexes

Cusumano, Alexander Q. [University of California, Los Angeles, CA (United States)]·Chaffin, Braden C. [University of California, Los Angeles, CA (United States)]·Cagan, David A. [California Institute of Technology (CalTech), Pasadena, CA (United States)] (ORCID:0000000247192789)·DiLuzio, Stephen [California Institute of Technology (CalTech), Pasadena, CA (United States)]·Sutcliffe, Erica [California Institute of Technology (CalTech), Pasadena, CA (United States)]·Hadt, Ryan G. [California Institute of Technology (CalTech), Pasadena, CA (United States)] (ORCID:0000000160261358)·Doyle, Abigail G. [University of California, Los Angeles, CA (United States)] (ORCID:0000000266410833)
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Abstract

Ni-catalyzed cross-coupling is a powerful strategy to forge C(sp 3 )–C(sp 3 ) bonds. Typically, to do so requires overcoming a challenging C–C bond-forming reductive elimination, often enabled by the intermediacy of highly oxidized Ni species or outer-sphere processes. While direct C(sp 3 )–C(sp 3 ) reductive elimination from the Ni II base oxidation state is normally thermally inaccessible, light-activation provides an avenue to affect such transformations. Here, we investigate the mechanism of light-induced C(sp 3 )–C(sp 3 ) bond formation from dialkyl bipyridine Ni II complexes through a variety of organometallic, spectroscopic, and computational studies. Wavelength-dependent quantum yields, ligand electronics–reactivity relationships, excited-state lifetimes, computed barriers, and product distributions from crossover studies support a photolysis/radical rebound mechanism. Furthermore, this reactivity paradigm complements existing strategies in the literature to promote reductive elimination from Ni II , such as the use of destabilizing, sterically hindered ligands and reduction of electron density at Ni through the binding of electron-deficient olefins. Hence, we envision that light-induced reductive elimination may enable the development of challenging C(sp 3 )–C(sp 3 ) couplings.

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AlkylsIrradiationLigandsMetal to ligand charge transferReductive elimination

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BibTeXRIS

Cusumano, Alexander Q. [University of California, Los Angeles, CA (United States)], Chaffin, Braden C. [University of California, Los Angeles, CA (United States)], Cagan, David A. [California Institute of Technology (CalTech), Pasadena, CA (United States)] (ORCID:0000000247192789), DiLuzio, Stephen [California Institute of Technology (CalTech), Pasadena, CA (United States)], Sutcliffe, Erica [California Institute of Technology (CalTech), Pasadena, CA (United States)], Hadt, Ryan G. [California Institute of Technology (CalTech), Pasadena, CA (United States)] (ORCID:0000000160261358), Doyle, Abigail G. [University of California, Los Angeles, CA (United States)] (ORCID:0000000266410833). 2025-08-26. Light-Promoted C(sp 3 )–C(sp 3 ) Reductive Elimination from Dialkyl NiII Complexes. https://doi.org/10.1021/jacs.5c09925

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