Dr. Robert Knowles

Abstract

The description and study of non-equilibrium processes continues to generate considerable interest in a wide variety of chemical disciplines. In line with these efforts, we have recently become interested in light-driven strategies for achieving out-of-equilibrium transformations for organic synthesis that operate through excited-state redox events. These electron transfer-based approaches provide a general mechanism for driving reactions in opposition to a thermodynamic gradient by selectively channeling the energy from photon-absorption events. However, they are applicable to a wider range of substrates and reaction types than direct excitation or energy transfer-based photochemical approaches. Several recent examples will be discussed, including the intermolecular anti-Markovnikov hydroamination of olefins¹, the isomerization of cyclic alcohols to linear carbonyl compounds via C-C bond cleavage², and light-driven catalytic deracemizations.³

References

1. Catalytic Intermolecular Hydroaminations of Unactivated Olefins with Secondary Alkyl Amines. Musacchio, A. J.; Lainhart, B. C.; Zhang, X.; Naguib, S. G.; Sherwood, T. C.; Knowles, R. R. Science, 2017, 355, 727–730

2. A Redox Strategy for Light-Driven, Out-of-Equilibrium Isomerizations and Application to Catalytic C–C Bond Cleavage Reactions. Ota, E.; Wang, H.; Frye, N. L.; R.; Knowles, R. R. J. Am. Chem. Soc. 2019, 141, 1457–1462.

3. Light-Diven Deracemization Enabled by Excited-State Electron Transfer. Shin, N. Y.; Ryss, J. M.; Zhang, X.; Miller, S. J.; Knowles, R. R. Science, 2019, 366, 364–369.v