1,2-Dicarbofunctionalization of Trifluoromethyl Alkenes with Pyridinium Salts via a Cycloaddition/Visible-Light-Enabled Fragmentation Cascade
Shujie Chen, Guo‐Shu Chen, Tao Deng, Jiahui Li, Zhiqing He, Liu Li-shan, Hai Ren, Yun‐Lin Liu
Abstract
Although trifluoromethyl alkenes have great synthetic potential, their 1,2-difunctionalization has been a challenge. In this Letter, we disclose the first 1,2-dicarbofunctionalization of trifluoromethyl alkenes with pyridinium salts via a cascade process involving a base-promoted [3 + 2] cycloaddition followed by a visible-light-mediated Norrish-type-II fragmentation. This protocol allows for the formation of pyridines bearing a trifluoromethyl-substituted quaternary center in moderate to excellent yields under mild conditions.
Topics & Concepts
TrifluoromethylChemistryPyridiniumCycloadditionFragmentation (computing)CascadeAlkenePhotochemistryMedicinal chemistryCombinatorial chemistryOrganic chemistryCatalysisOperating systemChromatographyComputer scienceAlkylFluorine in Organic ChemistryRadical Photochemical ReactionsCatalytic C–H Functionalization Methods