The electronic states and the spin-orbit couplings between them involved in the photodissociation process of the radical molecules CHX, CHX → CH + X (X = O, S), taking place after the Ã(A) ← X[combining tilde](E) transition, have been investigated using highly correlated ab initio techniques. A two-dimensional representation of both the potential-energy surfaces (PESs) and the couplings is generated. This description includes the C-X dissociative mode and the CH umbrella mode. Spin-orbit effects are found to play a relevant role in the shape of the excited state potential-energy surfaces, particularly in the CHS case where the spin-orbit couplings are more than twice more intense than in CHO. The potential surfaces and couplings reported here for the present set of electronic states allow for the first complete description of the above photodissociation process. The different photodissociation mechanisms are analyzed and discussed in light of the results obtained.
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http://dx.doi.org/10.1039/c7cp06054h | DOI Listing |
Angew Chem Int Ed Engl
January 2025
Shanghai Jiao Tong University, Frontiers Science Center for Transformative Molecules, 800 Dongchuan Road, 200240, Shanghai, CHINA.
Along with the renaissance of radical chemistry, the past decade has witnessed rapid development in radical-mediated rearrangement reactions. A wide diversity of radical approaches harnessing functional-group migration (FGM) have been devised to enhance both synthetic efficiency and molecular complexity. However, the application of FGM reactions to construct stereogenic centers remains underexplored owing to the inherent challenges of asymmetric radical reactions.
View Article and Find Full Text PDFOrg Lett
January 2025
School of Pharmacy, Hangzhou Normal University, Hangzhou, Zhejiang 311121, P. R. China.
We demonstrate here an efficient and facile Ni-catalyzed electrochemical cross-electrophile thiolation approach for readily available alkyl alcohols with pyridyl thioesters. This C(sp)-S bond-forming modular strategy displays extensive substrate adaptability and good functional group tolerance, which allows the production of a range of alkyl sulfides with specific chemoselectivity. Furthermore, the potential applications of this methodology are illustrated by last-stage modification of bioactive molecules and sulfinylative cross-couplings.
View Article and Find Full Text PDFChem Soc Rev
January 2025
Pingyuan Laboratory, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, Henan, P. R. China.
The use of olefins in the construction of cyclic compounds represents a powerful strategy for advancing the pharmaceutical industry. Photocycloaddition has attracted significant interest from chemists due to its ability to exploit simple and readily available olefins along with their reaction patterns under mild conditions. Moreover, the sustainable and versatile pathways for generating highly reactive intermediates can greatly enrich both substrate diversity and reaction patterns.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
School of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, 225002, Yangzhou, China.
As fundamental structural scaffolds in numerous natural products and pharmaceutical molecules, the construction of cyclohexenone architectures has remained a pivotal focus in organic chemistry. However, established strategies to synthesize cyclohexenone derivatives Dowd-Beckwith ring-expansion reaction invariably involve the use of transition metals and photoirradiation. Herein, we present a novel transition-metal- and photoirradiation-free pathway to access such structures from α-iodomethyl β-keto esters with electron-rich arenediazonium salts as inexpensive radical initiators and oxidants under mild reaction conditions.
View Article and Find Full Text PDFMater Today Bio
February 2025
Department of Neurosurgery, Research Center of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong University, Nantong, 226001, China.
Chemodynamic therapy (CDT) is an emerging antitumor strategy utilizing iron-initiated Fenton reaction to destroy tumor cells by converting endogenous HO into highly toxic hydroxyl radical (OH). However, the intratumoral overexpressed glutathione (GSH) and deficient acid greatly reduce CDT efficacy because of OH scavenging and decreased OH production efficiency. Even worse, the various physiological barriers, especially in glioma, further put the brakes on the targeted delivery of Fenton agents.
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