S-Arylation of Thioic S-Acid Using Thianthrenium Salts via Photoactivation of Electron Donor-Acceptor Complex.

Thioesters make up an important class of bioactive compounds. Due to their chemoselectivity, they have been widely used in the synthesis of a wide range of complex bioactive molecules and natural products. At present, chemists have developed a variety of methods for the preparation of thioester compounds. However, these methods usually require the use of transition metal catalysis or harsh reaction conditions. The strategy of synthesizing thioester compounds via visible light-induced electron donor-acceptor (EDA) complex reactions avoids the problems associated with conventional methods through the development of photocatalysis. Here we report a sustainable method for thiocarbonylating aryl sulfonium salts via a visible light-induced EDA complex process without transition metals.

Visible Light-Accelerated Palladium-Catalyzed Thiocarbonylation Using Oxalic Acid Monothioester with Aryl/Alkenyl Sulfonium Salts.

Herein, we present a decarboxylative thiocarbonylation of aryl and alkenyl sulfonium salts with oxalic acid monothioethers (OAMs), which can be achieved by visible light-accelerated palladium catalysis. Sulfonium salts are widely available, and OAM is an easily accessible and stored reagent; this mild reaction method can also be used for the synthesis of different types of thioester compounds. The reaction represents a new application of visible light-accelerated palladium catalysis in catalytic decarboxylative cross-couplings.