Single-atom-nickel photocatalytic site-selective sulfonation of enamides to access amidosulfones†
Abstract
Single-atom photocatalysis as an important organic transformation strategy has received increasing attention, with the performances largely depending on the design of catalysts. This protocol involves initially the fabrication of a single-atom photocatalyst Ni/TiO2 for the visible-light-induced site-selective sulfonation of enamides to give amidosulfones with 36 examples up to 99% yield. The experimental results show that this single-atom photocatalyst Ni/TiO2 can achieve site-selective sulfonation of enamide to construct α-amidosulfones and β-propionamidosulfones under visible light. Importantly, such a single-atom photocatalysis-based synthesis system exhibits favorable recyclability, high turnover number (up to 18 963), excellent tolerance of functional groups, and can be easily scaled up with good efficiency.