Journal ArticleDOI
Excited-state quenching by proton-coupled electron transfer
Javier J. Concepcion,M. Kyle Brennaman,Jeremy R. Deyton,Natalia V. Lebedeva,Malcolm D. E. Forbes,John M. Papanikolas,Thomas J. Meyer +6 more
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The protonated, reduced complex [Ru(bpy)2(bpzH•)]2+ functions as a H-atom reductant toward quinone or benzaldehyde with potential implications for net photochemistry and energy conversion.Abstract:
The emitting metal-to-ligand charge transfer (MLCT) excited state of [Ru(bpy)2(bpz)]2+ (bpy is 2,2‘-bipyridine; bpz is 2,2‘-bipyrazine) is reductively quenched by hydroquinone (H2Q) by proton-coupled electron transfer (PCET), most likely by concerted electron−proton transfer (EPT). The identity of the transient products ([Ru(bpy)2(bpzH•)]2+ and HQ•) and the kinetics of their formation and disappearance have been established by steady-state emission and time-resolved emission, absorption, and EPR measurements. The protonated, reduced complex [Ru(bpy)2(bpzH•)]2+ functions as a H-atom reductant toward quinone or benzaldehyde with potential implications for net photochemistry and energy conversion.read more
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Book ChapterDOI
Time-Resolved Electron Paramagnetic Resonance Spectroscopy: History, Technique, and Application to Supramolecular and Macromolecular Chemistry
TL;DR: The experimental technique of time-resolved (direct detection) electron paramagnetic resonance (TREPR) spectroscopy, and its role in the elucidation of free-radical structure, dynamics, and reactivity within the field of spin chemistry, is presented and discussed in this article.
Journal ArticleDOI
Kinetic Isotope Effects in Reductive Excited-State Quenching of Ru(2,2’-Bipyrazine)32+ by Phenols
TL;DR: In this article, electron transfer from phenol molecules to a photoexcited ruthenium(II) complex was investigated as a function of the para-substituent (R = OCH3, CH3, H, Cl, Br, CN) attached to the phenols.
Journal ArticleDOI
The photochemical alkylation and reduction of heteroarenes.
TL;DR: The functionalization of heteroarenes has been integral to the structural diversification of medicinally active molecules such as quinolines, pyridines, and phenanthridines.
Journal ArticleDOI
Aerobic Oxidation of Olefins and Lignin Model Compounds Using Photogenerated Phthalimide-N-oxyl Radical
Jian Luo,Jian Zhang +1 more
TL;DR: Using donor-substituted aromatic ketones, such as 4,4'-bis(diphenylamino)benzophenone (DPA-BP), PINO radicals are efficiently produced and subsequently utilized to functionalize olefins to afford a new class of alkyl hydroperoxides.
Journal ArticleDOI
Exploring the metric of excited state proton transfer reactions.
TL;DR: A computational protocol enabling one to locate possible reaction pathways for the ESPT is here proposed, based on the use of density based indices purposely developed to characterize the properties of vertical and relaxed excited states which allow one to discriminate the most favorable reaction paths on potential energy surfaces.
References
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Journal ArticleDOI
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Journal ArticleDOI
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