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Abstract Visible‐light‐driven C−C bond formation utilizing ketyl radical (Cketyl) species has attracted increasing attention recently, as it provides a direct route for the synthesis of complex molecules. However, the most‐developed homogeneous photocatalytic systems for the generation and utilization of ketyl radicals usually entail noble metal‐based (e. g., Ru and Ir) photosensitizers, which suffer from not only high cost but also potential degradation and hence pose challenges in product separation and purification. In contrast, readily accessible, inexpensive, and recyclable semiconductors represent a class of attractive and alternative photocatalysts but remain much less explored for photocatalytic ketyl radical initiated C−C bond formation. This work demonstrates that a wide range of industrially important chemicals, including substituted chromanes and tertiary alcohols, can be produced on ZnIn2S4under visible light irradiation through intramolecular cyclization (Cketyl−Csp2) and intermolecular cross‐coupling (Cketyl−Csp3) reactions, respectively, using ketyl radicals. A suite of experimental studies aided by computational investigation were carried out to shed light on the mechanistic insights of these two types of ketyl radical initiated C−C coupling reactions on ZnIn2S4.
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Zinc Indium Sulfide‐Based Photocatalysts for Selective Organic Transformations
Abstract The burgeoning field of semiconductor‐mediated organic conversion is of paramount significance, with zinc indium sulfide (ZnIn2S4) emerging as a standout candidate owing to its benign nature, optimal bandgap, extensive light absorption spectrum, remarkable physicochemical properties, and straightforward synthesis. This review examines the latest breakthroughs and the trajectory of ZnIn2S4‐based photocatalysts in the realm of selective organic transformation. We start with a distinct overview of the intrinsic physical attributes of ZnIn2S4and the underlying mechanisms driving its efficacy in photocatalytic organic transformations. Subsequently, the preparation methods of ZnIn2S4are summarized. The main focus is the state‐of‐the‐art photocatalytic application of various ZnIn2S4‐based photocatalysts, such as redox reactions, the construction of C−C, C−S and S−S bonds, and the cleavage of C−O, C−C, and C=C bonds. In the conclusion part, we provide our perspectives on the prospective advancements and the remaining challenges that lie ahead in the optimization of ZnIn2S4‐based photocatalysts, with the ultimate goal of enhancing their efficacy for a diverse array of photosynthetic applications. It is anticipated to inspire the strategic engineering of ZnIn2S4and other semiconductor‐based photocatalysts for various artificial photosynthesis reactions.
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- Award ID(s):
- 1955358
- PAR ID:
- 10642272
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemCatChem
- Volume:
- 16
- Issue:
- 13
- ISSN:
- 1867-3880
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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