Metal-Free and Visible Light-Induced Difunctionalizations of -CF₃ Styrenes with Aryl Diazonium Salts and Hetero Nucleophiles

Metal-free, visible light-induced difunctionalizations of alpha-CF3 styrenes with aryl diazonium salts and various hetero nucleophiles (ROH, H2O, N-3(-) and F-) are described. This concise protocol provided easy access to the alpha-CF3 tertiary alkyl ethers, alcohol and fluorides with good yields and excellent functional group tolerance. In addition, the four-component "SO2" insertion reaction also worked efficiently to produce the alpha-CF3, beta-sulfonyl ethers in moderate to good yields. A radical-polar crossover coupling pathway was proposed for the C-O bond formation.