Photocatalyzed Thiocarbamylationof Alkenyl Radicals via ThiopheneSalts

Abstract

Inrecent years, visible-light-induced transformations have taken a central role indriving forward the progress of modern organic synthesis. Despite the abundanceof synthetic strategies enabling access to aryl- and alkyl-centered radicals,the exploitation of photochemistry to generate highly reactive alkenyl radicalshas remained notably underdeveloped. Herein, we report a sustainable strategyfor generating alkenyl radicals based on a photocatalytic single-electrontransfer process. Through systematic optimization of conditions such asphotocatalysts, light sources, and additives, we confirmed that radicalreactions can efficiently occur under metal-free conditions usingstyrenylthiophene salt as radical donors, thiuram derivatives as radicalacceptors, and 4CzIPN (1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene) as the photocatalyst. This method is operationallysimple, environmentally friendly, and does not require the addition of preciousmetal reagents, providing a novel strategy for the methodology of alkenylradical generation.

Keywords

Photocatalysis / Radical / Synthesis

Supplementary Materials

The following supporting information can be found at: https://www.sciepublish.com/article/pii/887, Table S1: Screening of Light (Without PC); Table S2: Screening of Time; Table S3: Screening of equivalence ratio of 1a:2a; Table S4: Screening of equivalence ratio of 1a:2b; Table S5: Screening of time; Table S6: Screening of solvent without PC; Table S7: Control experiments of TMTM.

Acknowledgements

We extend our heartfelt gratitude to the School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, as well as Hubei Three Gorges Laboratory for projects support.

Author Contributions

Methodology, Formal Analysis, Investigation, Writing-Original Draft Preparation, B.-X.H.; Data Curation, Validation, Visualization, X.-Y.L. and J.-J.C.; Writing-Review & Editing, Supervision, Funding Acquisition, R.-A.C., Q.-W.H., Z.-P.G. and Z.-B.D.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

All data generated or analyzed during this study are included in this published article.

Funding

This work was supported by the National Natural Science Foundation of China (22401223), the Natural Science Foundation of Hubei Province (2024AFB315), the Science and Technology Research Project of Hubei Provincial Department of Education (Q20231501), the Open and Innovation Fund of Hubei Three Gorges Laboratory (SC240004, SK240010), the Innovation Project of Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education (LCX202403, LCX202504), the Open Research Fund of School of Chemistry and Chemical Engineering, the Henan Normal University (2020ZD02), the Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province (CSPC202306), the Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology (BM2012110), the Innovative Research Group Project of National Natural Science Foundation of Hubei (2025AFA049), and the Innovative Development Joint Fund of Natural Science Foundation of Hubei Province (2025AFD316), the Open Research Fund of Key Laboratory of Danjiangkou Reservoir Area’s Aquatic Eco-Environment and Health, Hanjiang Normal University (DK12505).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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