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Abstract The direct C−H acyloxylation of polycyclic aromatic hydrocarbons (PAHs) with carboxylic acids as the acyloxylating agents was achieved via the electron‐donor‐acceptor (EDA) complexes between PAHs andN‐iodosuccinimide (NIS). This visible light‐assisted metal‐free C−H acyloxylation reaction provides an easy access to the desired aryl carboxylates from readily available PAHs and aliphatic and aromatic carboxylic acids under mild reaction conditions. magnified image
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Catalyst‐Free Decarbonylative Trifluoromethylthiolation Enabled by Electron Donor‐Acceptor Complex Photoactivation
Abstract A catalyst‐ and additive‐free decarbonylative trifluoromethylthiolation of aldehyde feedstocks has been developed. This operationally simple, scalable, and open‐to‐air transformation is driven by the selective photoexcitation of electron donor‐acceptor (EDA) complexes, stemming from the association of 1,4‐dihydropyridines (donor) withN‐(trifluoromethylthio)phthalimide (acceptor), to trigger intermolecular single‐electron transfer events under ambient‐ and visible light‐promoted conditions. Extension to other electron acceptors enables the synthesis of thiocyanates and thioesters, as well as the difunctionalization of [1.1.1]propellane. The mechanistic intricacies of this photochemical paradigm are elucidated through a combination of experimental efforts and high‐level quantum mechanical calculations [dispersion‐corrected (U)DFT, DLPNO‐CCSD(T), and TD‐DFT]. This comprehensive study highlights the necessity for EDA complexation for efficient alkyl radical generation. Computation of subsequent ground state pathways reveals that SH2 addition of the alkyl radical to the intermediate radical EDA complex is extremely exergonic and results in a charge transfer event from the dihydropyridine donor to theN‐(trifluoromethylthio)phthalimide acceptor of the EDA complex. Experimental and computational results further suggest that product formation also occursviaSH2 reaction of alkyl radicals with 1,2‐bis(trifluoromethyl)disulfane, generated in‐situ through combination of thiyl radicals. magnified image
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- Award ID(s):
- 1827457
- PAR ID:
- 10233421
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Synthesis & Catalysis
- Volume:
- 363
- Issue:
- 14
- ISSN:
- 1615-4150
- Page Range / eLocation ID:
- p. 3507-3520
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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