Visible light-initiated radical 1,3-difunctionalization of β,γ-unsaturated ketones
- Sci Adv. 2022 Dec 9;8(49):eabq8596. doi: 10.1126/sciadv.abq8596.
- 1. State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao 266237, Shandong, P. R. China.
- 2. Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, Shandong, P. R. China.
- 3. Laboratory of Marine Drugs and Biological Products, Pilot National Laboratory for Marine Science and Technology, 168 Weihai Road, Qingdao 266237, Shandong, P. R. China.
Radical-mediated 1,2-difunctionalization of olefins is a well-established synthetic technique widely used in the rapid construction of structurally diverse molecular entities. However, radical-mediated 1,3-difunctionalization reactions are rare, and the substrates are generally limited to strained skeletons. Here, we report a practical approach for 1,3-difunctionalization of available β,γ-unsaturated ketones via a radical cascade process including visible light-irradiated radical addition, thermodynamic stability-driven 1,2-carbonyl migration from unactivated all-carbon quaternary center, and terminal C-radical varied transformations. Various highly functionalized alkyl skeletons with different valuable functional groups at positions 1 and 3 and the carbonyl group at position 2 have been synthesized through a radical chain pathway or Cu-catalyzed Ritter-type reaction. Moreover, this protocol provides a real case of diversity-oriented radical rearrangement for drug discovery. We identified a previously unknown chemotype of dual inhibitors for hypoxia-inducible factor (HIF) and Wnt signaling pathways from products. These small-molecule inhibitors could suppress HIF and Wnt signaling-dependent HCT116 cell growth in 2D and 3D culture systems.